List of rivers of Wales
Encyclopedia
This is a list of rivers of Wales
, organised geographically, taken anti-clockwise, from Hoylake
on Wirral
through to the M48 Bridge
that separates the estuary of the River Wye
from the River Severn
.
Tributaries are listed down the page in an upstream direction, starting with those closest to the sea. The main stem
(or principal) river of a catchment is given, left-bank tributaries are indicated by (L), right-bank tributaries by (R). Note that in general usage, the 'left (or right) bank of a river' refers to the left (or right) hand bank, as seen when looking downstream. Where a named river splits (when viewed upstream) into two differently named rivers these are labelled as (Ls) and (Rs) for the left and right forks. A prime example is the split of the River Taff
into the Taf Fawr and the Taf Fechan at Cefn Coed-y-cymmer.
The list is essentially a list of the main river
s of Wales (as defined by the Environment Agency
) and which more or less includes every watercourse named on Ordnance Survey
mapping. Difficulties arise otherwise in determining what should and what should not be included.
Certain names are encountered frequently and particular care should be taken to differentiate between the various occurrences of Clydach, Clywedog and of Dulas for example as well as those whose names refer perhaps to the colour of their waters e.g. Afon Goch (red river), Afon Ddu (black/dark river ) and Afon Wen (white/light river).
Note "Afon Menai", known as the "Menai Strait
" in English, is not technically a river, despite its Welsh name..
In Wales, flowing into the Irish Sea
From Bangor Pier
to St. Govan's Head
In Wales, flowing into the Bristol Channel
From St. Govan's Head to M48 Bridge
Rivers only partly in Wales are included in this table in italics. Note that river lengths given by different authorities vary due to the different ways in which the measurement is made or indeed estimated. That rivers are partly fractal in nature accounts for some variation and lengths can also vary slightly over time as meanders expand or are cut off where rivers run through broad flood-plains.
Wales
Wales is a country that is part of the United Kingdom and the island of Great Britain, bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km²...
, organised geographically, taken anti-clockwise, from Hoylake
Hoylake
Hoylake is a seaside town within the Metropolitan Borough of Wirral, on Merseyside, England. It is located at the north western corner of the Wirral Peninsula, near to the town of West Kirby and where the River Dee estuary meets the Irish Sea...
on Wirral
Wirral Peninsula
Wirral or the Wirral is a peninsula in North West England. It is bounded by three bodies of water: to the west by the River Dee, forming a boundary with Wales, to the east by the River Mersey and to the north by the Irish Sea. Both terms "Wirral" and "the Wirral" are used locally , although the...
through to the M48 Bridge
Severn Bridge
The Severn Bridge is a suspension bridge spanning the River Severn between South Gloucestershire, just north of Bristol, England, and Monmouthshire in South Wales, via Beachley, a peninsula between the River Severn and River Wye estuary. It is the original Severn road crossing between England and...
that separates the estuary of the River Wye
River Wye
The River Wye is the fifth-longest river in the UK and for parts of its length forms part of the border between England and Wales. It is important for nature conservation and recreation.-Description:...
from the River Severn
River Severn
The River Severn is the longest river in Great Britain, at about , but the second longest on the British Isles, behind the River Shannon. It rises at an altitude of on Plynlimon, Ceredigion near Llanidloes, Powys, in the Cambrian Mountains of mid Wales...
.
Tributaries are listed down the page in an upstream direction, starting with those closest to the sea. The main stem
Main Stem
"Main Stem" is 1942 instrumental by Duke Ellington and His Famous Orchestra. Although recorded in 1942, the single would not be released until 1944 where it was Duke Ellington's last of four number one's on the Harlem Hit Parade. "Main Stem" would also peak at number twenty on the pop chart"Main...
(or principal) river of a catchment is given, left-bank tributaries are indicated by (L), right-bank tributaries by (R). Note that in general usage, the 'left (or right) bank of a river' refers to the left (or right) hand bank, as seen when looking downstream. Where a named river splits (when viewed upstream) into two differently named rivers these are labelled as (Ls) and (Rs) for the left and right forks. A prime example is the split of the River Taff
River Taff
The River Taff is a large river in Wales. It rises as two rivers in the Brecon Beacons — the Taf Fechan and the Taf Fawr — before joining to form the Taff north of Merthyr Tydfil...
into the Taf Fawr and the Taf Fechan at Cefn Coed-y-cymmer.
The list is essentially a list of the main river
Main river
Main rivers are a statutory type of watercourse in England and Wales, usually larger streams and rivers, but also include some smaller watercourses. A main river is defined as a watercourse marked as such on a main river map, and can include any structure or appliance for controlling or regulating...
s of Wales (as defined by the Environment Agency
Environment Agency
The Environment Agency is a British non-departmental public body of the Department for Environment, Food and Rural Affairs and an Assembly Government Sponsored Body of the Welsh Assembly Government that serves England and Wales.-Purpose:...
) and which more or less includes every watercourse named on Ordnance Survey
Ordnance Survey
Ordnance Survey , an executive agency and non-ministerial government department of the Government of the United Kingdom, is the national mapping agency for Great Britain, producing maps of Great Britain , and one of the world's largest producers of maps.The name reflects its creation together with...
mapping. Difficulties arise otherwise in determining what should and what should not be included.
Certain names are encountered frequently and particular care should be taken to differentiate between the various occurrences of Clydach, Clywedog and of Dulas for example as well as those whose names refer perhaps to the colour of their waters e.g. Afon Goch (red river), Afon Ddu (black/dark river ) and Afon Wen (white/light river).
Dee catchment
- River Dee, WalesRiver Dee, WalesThe River Dee is a long river in the United Kingdom. It travels through Wales and England and also forms part of the border between the two countries....
(Afon Dyfrdwy)- Nant-y-fflint (L) (flows into Dee EstuaryDee EstuaryThe Dee Estuary is a large estuary by means of which the River Dee flows into Liverpool Bay. The estuary starts near Shotton after a five miles 'canalised' section and the river soon swells to be several miles wide forming the boundary between the Wirral Peninsula in north-west England and...
) - Wepre Brook (L) (flows into Dee Estuary)
- Aldford BrookAldford BrookAldford Brook is a short river in Cheshire, England. It is a tributary of the River Dee, and joins the Dee at the village of Aldford....
(R) (wholly in England) - River AlynRiver AlynThe River Alyn is a tributary of the River Dee. The River Alyn rises at the southern end of the Clwydian hills and the Alyn Valley forms part of the Clwydian Range Area of Outstanding Natural Beauty...
(L) (Afon Alun / River Alun)- River CegidogRiver CegidogThe River Cegidog is a river in north-east Wales. It flows mainly through Flintshire but towards the end of its course it forms the border between Flintshire and Wrexham County Borough....
(R) (Afon Cegidog)- Nant-y-FfrithNant-y-FfrithNant-y-Ffrith refers to a stream and the wooded valley through which it flows on the border between Flintshire and Wrexham County Borough in Wales. The stream begins in moorland to the east of Llandegla. It passes Bwlchgwyn village before entering a rather steep-sided, rocky valley...
(R)
- Nant-y-Ffrith
- River TerrigRiver TerrigThe River Terrig is a small river in north-east Wales.The river rises at Llyn Cyfynwy near Graianrhyd village in the community of Llanarmon-yn-Ial, Denbighshire, about three miles from the source of the River Alyn. It then flows northwards and eastwards, forming the boundary between the old...
(R) (Afon Terrig)
- River Cegidog
- Worthenbury Brook (R)
- Emral Brook (Ls)
- Wych BrookWych BrookThe Wych Brook or Red Brook, formerly known as the River Elfe, is a small river in the north-west midlands of the United Kingdom. It forms both the historic and present-day border between England and Wales...
(Rs) (formerly known as the "River Elfe")- Red Brook (L)
- River ClywedogRiver ClywedogThe River Clywedog in the county borough of Wrexham, Wales has always been the lifeblood of the area, watering crops and livestock since early times, powering corn mills and driving industrial machinery...
(L) (Afon Clywedog)- River GwenfroRiver GwenfroThe River Gwenfro is a small river in Wrexham County Borough, north Wales. It is a tributary of the Clywedog. The name Gwenfro is possibly derived from the Welsh language words gwen , "white", and bro, "border", "boundary"....
(L) (Afon Gwenfro) - Glanyrafon Brook (R)
- Black Brook (R) (Afon Ddu)
- River Gwenfro
- Shell Brook (R)
- River CeiriogRiver CeiriogThe River Ceiriog is a river in north east Wales. It is a tributary of the River Dee. It rises on the south east slopes of Moel Fferna in the Berwyn Mountains, and flows through the Ceiriog Valley in Wrexham County Borough. It flows below Chirk Castle and the town of Chirk, where the Chirk...
(R) (Afon Ceiriog) (head of river is Ceiriog Ddu)- River Teirw (L) (Afon Teirw)
- Nant Sarffle (R)
- Nant Cwm-y-geifr (R)
- Nant Cwm-llawenog (R)
- Nant Rhydwilym (R)
- River EithaRiver EithaThe River Eitha is a small river in Wrexham County Borough, Wales. It is part of the River Dee catchment. Its name was probably derived from the Welsh word eithaf - "extremity", "farthest"....
(L) (Afon Eitha) - Eglwyseg River (L)
- Afon Morwynion (L)
- River Alwen (L) (Afon Alwen)
- Afon Ceirw (R)
- Merddwr (R) (known as Nant Lleidiog upstream)
- Afon Medrad (R)
- Afon Brenig (L)
- Afon Trystion (R)
- Afon Llynor (R)
- Afon Ceidiog (R)
- Hirnant (R)
- Afon TrywerynAfon TrywerynFor the flooding of the Tryweryn Valley, see Llyn Celyn.The Tryweryn is a river in north Wales which starts at Llyn Tryweryn in the Snowdonia National Park and after joins the river Dee at Bala. It is one of the main tributaries of the Dee and has been dammed to form Llyn Celyn...
(L) (River Tryweryn)- Afon MynachAfon MynachThe Afon Mynach is a small river in Ceredigion, Wales.Its source is at the meeting of two smaller rivers, the Nant Rhuddnant and the Afon Merin...
(L) - Afon Hesgyn (L)
- Afon Gelyn (L) (flows into Llyn CelynLlyn CelynLlyn Celyn is a large reservoir constructed between 1960 and 1965 in the valley of the River Tryweryn in Gwynedd, North Wales. It measures roughly 2½ miles long by a mile wide, and has a maximum depth of...
) - Nant Aberderfel (R) (flows into Llyn Celyn)
- Afon Mynach
- Afon Llafar (L) (flows into Bala LakeBala LakeBala Lake is a large lake in Gwynedd, Wales. It was the largest natural body of water in Wales prior to the level being raised by Thomas Telford to help support the flow of the Ellesmere Canal. It is long by wide, and is subject to sudden and dangerous floods. The River Dee runs through it and...
) - Afon TwrchAfon TwrchThe Afon Twrch is a river which rises in the Black Mountain in south Wales. It forms the boundary between the counties of Powys and Carmarthenshire and, downstream of Ystradowen, between Powys and Neath Port Talbot county borough.The headwaters arise on the southern slopes of Bannau Sir Gaer and...
(R) - Afon Lliw (L)
- Nant-y-fflint (L) (flows into Dee Estuary
Clwyd catchment
- River ClwydRiver ClwydThe River Clwyd is a river in North Wales which rises in the Clocaenog Forest northwest of Corwen.It flows due south until at Melin-y-Wig it veers northeastwards, tracking the A494 to Ruthin. Here it leaves the relatively narrow valley and enters a broad agricultural vale, the Vale of Clwyd...
(Afon Clwyd)- Afon Gele (L)
- River ElwyRiver ElwyThe River Elwy is a river in North Wales and is a tributary of the River Clwyd. The source of the river is sometimes said to be on the northern flank of Moel Seisiog, south-east of Llanrwst, at Ordnance Survey grid reference SH853593...
(L) (Afon Elwy)(Also known as Afon Cledwen above the village of Llangernyw)- Afon Meirchion (R)
- River Aled (R)
- Afon Gallen (Ls)
- River Wheeler (R) (Afon Chwiler)
- Afon Ystrad (R)
- River Clywedog (Clwyd) (L) (Afon Clywedog) (Not to be confused with the Dee tributary of the same name)
Conwy catchment
- River ConwyRiver ConwyThe River Conwy is a river in north Wales. From its source to its discharge in Conwy Bay it is a little over long. "Conwy" is sometimes Anglicized as "Conway."...
(Afon Conwy)- Afon Gyffin (L)
- Afon RoeAfon RoeThe Afon Roe is a small river in Snowdonia, north Wales.Its tributary is the Afon Tafolog, which drains the eastern slopes of Drum, a mountain in the Carneddau range.The river flows through the village of Rowen before joining the River Conwy....
(L) (known as Afon Tafolog in upper reaches) - Afon DulynAfon DulynAfon Dulyn is the outflow from Llyn Dulyn, a lake in the Carneddau mountains in North Wales. It is a tributary of the river Conwy....
(L)- Afon DduAfon Ddu' is the name of several rivers in Snowdonia, North Wales.One flows from Llyn Cowlyd on the south-eastern edge of the Carneddau range to join the river Conwy, passing Pont Dolgarrog on the B5106 road, just south of the village of Dolgarrog. The gorge cut by the river at this point is popular for...
(L) - Afon Garreg-wen (L)
- Ffrwd Cerriguniawn (L)
- Afon MelynllynAfon MelynllynAfon Melynllyn is the outflow from Llyn Melynllyn, a lake in the Carneddau mountains in North Wales. It is a tributary of Afon Dulyn, itself a tributary of the river Conwy....
(R)
- Afon Ddu
- Afon Porth-llwydAfon Porth-llwydAfon Porth-llwyd is a river in Snowdonia, North Wales. It flows from Llyn Eigiau on the south-eastern edge of the Carneddau range to join the river Conwy.Its waters are trapped at Coedty reservoir before flowing down to pass under Pont Newydd in Dolgarrog...
(L) - Afon DduAfon Ddu' is the name of several rivers in Snowdonia, North Wales.One flows from Llyn Cowlyd on the south-eastern edge of the Carneddau range to join the river Conwy, passing Pont Dolgarrog on the B5106 road, just south of the village of Dolgarrog. The gorge cut by the river at this point is popular for...
(L) - Afon Crafnant (L)
- Afon Geirionydd (R)
- Afon Gallt y Gwg (R)
- Nant y Goron (R)
- Afon Llugwy (L)
- Nantygwryd (R)
- Afon Lledr (L)
- Afon Wybrnant (R)
- Afon Maesgwm (R)
- Afon Ystumiau (L)
- Afon Machno (L)
- Afon Glasgwm (L)
- Afon Iwrch (R)
- Afon Eidda (L)
- Merddwr (R)
- Afon Caletwr (R)
- Afon Serw (R)
Simple coastal catchments
- Afon Gyrach
- Afon DduAfon Ddu' is the name of several rivers in Snowdonia, North Wales.One flows from Llyn Cowlyd on the south-eastern edge of the Carneddau range to join the river Conwy, passing Pont Dolgarrog on the B5106 road, just south of the village of Dolgarrog. The gorge cut by the river at this point is popular for...
- Afon Glan-sais (L)
- Afon Maes-y-bryn (R)
Aber catchment
- Afon AberAfon AberThe Afon Aber is a small river in Gwynedd that enters Liverpool Bay on the coast of North Wales at Abergwyngregyn, . It rises in the Carneddau mountains on the northern watersheds of Drum, Foel Fras and Garnedd Uchaf and the eastern watersheds of Drosgl and Moel Wnion...
- Afon Anafon (Rs)
- Afon Rhaeadr Fawr (Ls)
- Afon Rhaeadr Bach (Ls)
- Afon Gam (L)
- Afon Goch (Rs)
- Afon Rhaeadr Bach (Ls)
Ogwen catchment
- Afon Ogwen
- Afon Caseg (R)
- Afon LlafarAfon LlafarAfon Llafar is a river in the Carneddau, Snowdonia. It rises where many streams flow down the slopes of Yr Elen, Carnedd Llewelyn and Carnedd Dafydd to join together in the valley below the cliffs of Ysgolion Duon . It is one of several similarly named streams in Wales...
(L) - Afon Denau (flows into Llyn OgwenLlyn OgwenLlyn Ogwen is a lake in north-west Wales. It lies alongside the A5 road between two mountain ranges of Snowdonia, the Carneddau and the Glyderau...
)- Nant Gwern y Gof (L)
- Afon LloerAfon LloerAfon Lloer is a small river in Snowdonia, North Wales. It is the outflow from Ffynnon Lloer, a lake in the Carneddau mountains, and it flows into Llyn Ogwen....
(flows into Llyn OgwenLlyn OgwenLlyn Ogwen is a lake in north-west Wales. It lies alongside the A5 road between two mountain ranges of Snowdonia, the Carneddau and the Glyderau...
)
- Afon Llafar
- Afon Caseg (R)
Minor coastal catchments
- Afon CadnantAfon CadnantThe Afon Cadnant is a small river on Anglesey, North Wales draining to the Menai Strait about 1 km north-east of the Menai Suspension Bridge...
(River Cadnant) - Nant Meigan
- Lleiniog
- Afon Nodwydd
- Afon y Marchogion
- Afon Lligwy
- Nant Perfedd
- Afon Goch (Dulas)
- Nant y Beddyw
- Afon Bryn Gwyn
- Afon Goch (Amlwch)
- Afon Wygyr
- Gwter Fudr
- Afon AlawAfon AlawThe Afon Alaw is a river on Anglesey which rises near Llanerchymedd and flows northwards into the reservoir of Llyn Alaw. Below the dam it then flows southwestwards to the island's west coast near Llanfachraeth. Its lower reaches, west of the A5025 road, are tidal.-References:...
(River Alaw)
Ffraw catchment
- Afon Ffraw
- Afon Frechwen (L)
- Afon Gwna (flows into Llyn Coron)
Cefni catchment
- Afon CefniAfon CefniAfon Cefni is one of the major rivers on the island of Anglesey, Wales. It is long. The river starts at the Llyn Cefni in the centre of the island and then runs south through the county town of Llangefni. Just north of the A55 the river turns and flows south-west. It passes through the flatlands...
(River Cefni)- Afon Newydd (L)
- Afon Ceint (L)
- Afon Erddreiniog (L) (flows into Cefni Reservoir)
Braint (ii) catchment
- Afon Braint (LlanfairPG)
- Afon Rhyd Eilian (L)
Note "Afon Menai", known as the "Menai Strait
Menai Strait
The Menai Strait is a narrow stretch of shallow tidal water about long, which separates the island of Anglesey from the mainland of Wales.The strait is bridged in two places - the main A5 road is carried over the strait by Thomas Telford's elegant iron suspension bridge, the first of its kind,...
" in English, is not technically a river, despite its Welsh name..
In Wales, flowing into the Irish SeaIrish SeaThe Irish Sea separates the islands of Ireland and Great Britain. It is connected to the Celtic Sea in the south by St George's Channel, and to the Atlantic Ocean in the north by the North Channel. Anglesey is the largest island within the Irish Sea, followed by the Isle of Man...
From Bangor PierBangor, Gwynedd
Bangor is a city in Gwynedd, north west Wales, and one of the smallest cities in Britain. It is a university city with a population of 13,725 at the 2001 census, not including around 10,000 students at Bangor University. Including nearby Menai Bridge on Anglesey, which does not however form part of...
to St. Govan's Head
Seiont catchment
- Afon Seiont (River Seiont) (known as Afon Rhythallt above Pont-Rhythallt)
- Afon Nant Peris (flows into Llyn Peris)
- Afon Arddu (L)
- Afon Nant Peris (flows into Llyn Peris)
Simple coastal catchments
- Afon Llifon
- Afon LlyfniAfon LlyfniThe Afon Llyfni is a small river in North Wales which arises as Nant Drws y Coed between Mynydd Mawr and Mynydd Drws-y-Coed just to the west of Snowdon....
, Lleyn - Afon Desach
- Afon Saint
- Afon Daron
Rhyd-hir catchment etc
- Afon Rhyd-hir
- Afon Penrhos (R)
- Afon Erch
- Afon WenAfon WenAfon Wen is a small hamlet on the Llŷn peninsula in the Welsh principal area of Gwynedd.- Location :It is located at the mouth of the Afon Wen river, half a mile from the village of Chwilog and midway between Pwllheli and Cricieth.- History & Amenities :...
Glaslyn catchment
- Afon Glaslyn
- Afon Dwyryd (L) (Headwaters are disputed to be the Afon Goedol)
- Afon y Glyn (L)
- Afon Prysor (L)
- Afon Cynfal (L)
- Afon Teigl (Ls)
- Afon Dylif
- Afon Croesor (L)
- Nanmor (L)
- Afon Colwyn (R)
- Afon Llynedno (L)
- Afon Dwyryd (L) (Headwaters are disputed to be the Afon Goedol)
Mawddach catchment
- Afon Mawddach
- Afon Dwynant (R)
- Afon Gwynant (L)
- Afon Cwm-llechen (R)
- Afon Cwm-mynach (R)
- Afon Wnion (L)
- Afon Clywedog (L)
- Afon Celynog (L)
- Afon WenAfon WenAfon Wen is a small hamlet on the Llŷn peninsula in the Welsh principal area of Gwynedd.- Location :It is located at the mouth of the Afon Wen river, half a mile from the village of Chwilog and midway between Pwllheli and Cricieth.- History & Amenities :...
(L) - Afon Gamlan (R)
- Afon Eden (R)
- Afon Crawcwellt (R)
- Afon Gain (R)
Dysynni catchment
- Afon Dysynni (R)
- Afon FathewAfon FathewThe Afon Fathew is a river in Gwynedd, north-west Wales. The river is downstream from the Dolgoch Falls which is a popular nature site.- Source :The Afon Fathew flows from near Dolgoch and joins the Dysynni to the east of Tywyn near Bryncrug....
(L) - Afon Cadair (R)
- Nant Gwernol (L)
- Afon Fathew
Dyfi catchment
- Afon DyfiRiver DyfiThe River Dyfi is a river in Mid Wales. The Dyfi estuary forms the border between the counties of Gwynedd and Ceredigion.- Source :...
(River Dovey)- Afon LeriAfon LeriThe Afon Leri is a river in Ceredigion, Wales. It rises at Llyn Craig-y-Pistyll and is joined at Talybont by Afon Ceulan before passing behind Borth to its mouth in the Dyfi estuary at Ynyslas....
(L)- Afon Ceulan (R)
- Afon Einion (L)
- Afon Llyfnant (L)
- Afon DulasAfon DulasThe Afon Dulas is a river forming the border between the counties of Gwynedd and Powys in Wales.Prior to local government reorganisation it formed the boundary between Sir Meirionnydd/Merionethshire and Sir Drefaldwyn/Montgomeryshire.-Route:It rises from a source in the hills above Aberllefenni...
(R) (North Dulas)- Afon Deri (R)
- Afon DulasAfon DulasThe Afon Dulas is a river forming the border between the counties of Gwynedd and Powys in Wales.Prior to local government reorganisation it formed the boundary between Sir Meirionnydd/Merionethshire and Sir Drefaldwyn/Montgomeryshire.-Route:It rises from a source in the hills above Aberllefenni...
(L) (South Dulas) - Afon TwymynAfon TwymynThe River Twymyn is a river in Powys, Mid Wales.From its source at the 40-metre high Ffrwd Fawr waterfall and head of the Pennant Valley near Dylife the river flows through Llanbrynmair before joining the River Dyfi upstream of Cemmaes Road.- See also :* Dylife Gorge...
(L)- Afon Rhiwsaeson (R)
- Afon Laen (L)
- Afon Rhiwsaeson (R)
- Afon Angell (R)
- Afon Cleifion (L)
- Afon Dugoed (Rs)
- Afon TafologAfon TafologThe Afon Tafalog is a small river in Snowdonia, north Wales. It is fed by a number of streams which drain the eastern slopes of Drum, a mountain in the Carneddau range....
(Ls)
- Afon Cerist (R)
- Afon Cywarch (R)
- Afon Leri
Clarach catchment
- Afon ClarachAfon ClarachThe Afon Clarach is a small river discharging into Cardigan Bay north of Aberystwyth. It flows through a largely agricultural and forested landscape except in its lowest reaches where its banks are crowded with holiday developments...
(formed at the confluence of Afon Stewi and Nant Silo)- Bowstreet Brook (R)
- Afon Peithyll (Ls)
Rheidol catchment
- River Rheidol (Afon Rheidol)
- Afon Melindwr (R)
- River Mynach (L) (Afon Mynach)
- Afon Merin (Rs)
- Nant Rhuddnant (Ls)
- Afon Castell (L)
- Afon Llechwedd Mawr (flows into Nant y Moch Reservoir)
- Afon Lluestgota (R)
- Afon Hengwm (flows into Nant y Moch Reservoir)
- Afon Hyddgen (R)
- Nant-y-mochNant-y-moch ReservoirNant-y-moch Reservoir is situated in the Cambrian Mountains in northern Ceredigion, Wales. The reservoir which flooded a part of the valley of the River Rheidol and its headwaters derives its name from a stream, the Nant-y-moch , which formerly flowed into the River Rheidol at this spot. The dam...
(stream flowing into Nant-y-moch Reservoir)
Ystwyth catchment
- River YstwythRiver YstwythThe River Ystwyth is a river in the county of Ceredigion, Wales. Its source is a number of streams that include the Afon Diliw, located on the border of Ceredigion and Powys in the Cambrian Mountains....
(Afon Ystwyth)- Afon Fâd (L)
- Afon Llanfihangel (R)
- Nant Cynon (Ls)
- Afon Magwr (R)
- Nant Freuo (L)
- Nant Pant-yr-Haidd (R)
- Nant Cwmtarw (L)
- Nant Cwm-nel (L)
- Nant Cilmeddu (L)
- Nant y Henfelin (L)
- Nant yr Brithyll (R)
- Nant y Berws (L)
- Nant Cell (R)
- Nant Lledwenau (R)
- Nant Bwlchgwallter (L)
- Nant Peiran (R)
- Nant Crafanglach (R)
- Nant Perfedd (L)
- Nant Ffrin-fawr (Rs)
- Nant Hylles (L)
- Nant Gau (L)
- Nant Ffrwd-ddu (L)
- Nant Cae-glas (R)
- Nant y Gwndwn-gwyn (Ls)
- Nant Cwta (Rs)
- Nant Milwyn (L)
- Nant Byr (L)
- Nant y Gwaith (R)
- Nant Watcyn (R)
- Nant yr Onnen (R)
- Nant Cwm-du (L)
- Nant Stwc (R)
- Nant Penygwndwn (L)
- Nant Garw (R)
- Nant y Cae Isaf (L)
- Nant y Cae (L)
- Nant Troedyrhiw (R)
- Afon Diliw (R)
- Nant yr Gafod (R)
- Diliw Fechan (R)
- Nant y Caseg (L)
- Nant yr Eglwys
- Nant yr Eglwys-fach (L)
- Nant Lwyd (R)
- Nant y Gorlan (Rs)
- Nant Llychese (R)
- Nant Rhydyfelin (L)
- Nant Ffos-casaf (L)
Wyre catchment
- Afon Wyre
- Afon Carrog (R)
- Wyre Fach (L)
- Nant Rhydrosser (L)
- Afon Tryal (L)
- Afon Beidog (L)
Teifi catchment
- River TeifiRiver TeifiThe River Teifi forms the boundary between the counties of Ceredigion and Carmarthenshire in south-west Wales for most of its 75 mile length, flowing into the sea below the town of Cardigan. The catchment of the river is estimated to be 1,008 square kilometres yielding an average flow at Glan...
(Afon Teifi)- Afon Piliau (L)
- Nant Arberth (R)
- Afon CychAfon CychAfon Cych is a small river tributary to the River Teifi in south-west Wales. Its "official" source is at Blaencych . It flows north-westwards through a deep, wooded, secluded valley, and joins the River Teifi at Abercych . Its total length is 13 km...
(L)- Afon DulasAfon DulasThe Afon Dulas is a river forming the border between the counties of Gwynedd and Powys in Wales.Prior to local government reorganisation it formed the boundary between Sir Meirionnydd/Merionethshire and Sir Drefaldwyn/Montgomeryshire.-Route:It rises from a source in the hills above Aberllefenni...
(L) - Afon Pedran (L)
- Afon Sylgen (R)
- Afon Dulas
- Afon Hirwaun (R)
- Afon Ceri (R)
- Afon DulasAfon DulasThe Afon Dulas is a river forming the border between the counties of Gwynedd and Powys in Wales.Prior to local government reorganisation it formed the boundary between Sir Meirionnydd/Merionethshire and Sir Drefaldwyn/Montgomeryshire.-Route:It rises from a source in the hills above Aberllefenni...
(R) - Afon Bedw (L)
- Afon Dulas
- Nant Bargod (L)
- Afon Tyweli (L)
- Afon Talog (R)
- Afon Clettwr (P)
- Clettwr Fawr (Rs)
- Clettwr Fach (Ls)
- Nant Cledlyn (R)
- Afon Duar (L)
- Afon Granell (R)
- Afon DulasAfon DulasThe Afon Dulas is a river forming the border between the counties of Gwynedd and Powys in Wales.Prior to local government reorganisation it formed the boundary between Sir Meirionnydd/Merionethshire and Sir Drefaldwyn/Montgomeryshire.-Route:It rises from a source in the hills above Aberllefenni...
(R)- Afon Denys (R)
- Nant Clywedog (L)
- Clywedog-isaf (Ls)
- Clywedog-ganol (Rs)
- Clywedog-uchaf (R)
- Afon Brefi (L)
- Nant Bryn-maen (R)
- Afon Berwyn (L)
- Afon Groes (R)
- Afon Fflur (L)
- CamddwrCamddwrThe Camddwr is a significant right-bank tributary of the River Towy in the eastern part of Ceredigion, mid Wales. It rises on the undulating plateau east of Garn Gron and flows in a generally south-southeasterly direction into Llyn Brianne, a reservoir formed by the damming of the upper Towy A...
(R) - Afon Meurig (R)
- Nant Lluest (R)
- Glasffrwd (L)
- Nant Egnant (L)
- Nant Rhydol (R)
Nyfer catchment etc
- Afon NyferAfon NyferThe Afon Nyfer is a river in North Pembrokeshire, West Wales which runs into the Irish Sea.The river rises at Blaencwm , just east of Crymych. It flows northward then westward, skirting the slopes of the Preseli Hills. It passes through Felindre Farchog and Nevern, and reaches the sea at Newport...
- Nant Duad (R)
- Afon Brynberian (L)
- Afon Bannon (L)
Minor coastal catchments
- River GwaunRiver GwaunThe River Gwaun is a river in Pembrokeshire, West Wales, which flows principally westwards draining to the sea into Fishguard Bay at Fishguard....
(Afon Gwaun)- River Aer (L)
- River AlunRiver Alun, PembrokeshireThe River Alun is a small river in northwestern Pembrokeshire, West Wales which rises near Tretio Common and flows southwestwards past the city of St David's to empty into St Bride's Bay at the rocky inlet of Porth Clais.- References :...
- Afon Solfach (River Solva)
- Brandy Brook
Cleddau catchment
- Daugleddau (estuary is Daugleddyf or Milford Haven downstream)
- Pembroke RiverPembroke RiverThe Pembroke River flows through south Pembrokeshire, Wales and flows in to Milford Haven at Pennar Mouth.-External links:***...
(L) - Carew River (L)
- Cresswell River (L)
- Western Cleddau (Rs)
- Millin Brook (L)
- Merlin's Brook (R)
- Cartlett Brook (L)
- Knock Brook (R)
- Camrose Brook (R)
- Rudbaxton Water (L)
- Spittal Brook (L)
- Nant-y-coy Brook (R)
- Afon Anghof (L)
- Afon Glan-rhyd (R)
- Nant y Bugail (L)
- Afon Cleddau (upper reaches of Western Cleddau)
- Eastern Cleddau (Ls)
- Afon Syfynwy (R)
- Afon Wern (R)
- Pembroke River
In Wales, flowing into the Bristol ChannelBristol ChannelThe Bristol Channel is a major inlet in the island of Great Britain, separating South Wales from Devon and Somerset in South West England. It extends from the lower estuary of the River Severn to the North Atlantic Ocean...
From St. Govan's Head to M48 BridgeSevern Bridge
The Severn Bridge is a suspension bridge spanning the River Severn between South Gloucestershire, just north of Bristol, England, and Monmouthshire in South Wales, via Beachley, a peninsula between the River Severn and River Wye estuary. It is the original Severn road crossing between England and...
Tâf catchment
- Afon TâfRiver TâfThe River Tâf is a river that rises in the Preseli Hills of North Pembrokeshire, West Wales, near the village of Crymych and is around 50 km long....
- Afon CywynRiver CywynThe River Cywyn is a river that flows through Carmarthenshire, south Wales. It rises some seven miles west-north-west of Carmarthen and flows in a southerly direction to join the River Tâf near its estuary....
(L) - Afon Cynin (L)
- Afon Dewi Fawr (L)
- Afon Sien (R)
- Afon Fenni (R)
- Afon Gronw (L)
- Afon MarlaisAfon Marlais, PembrokeshireThe Afon Marlais is a right-bank tributary of the River Tâf in Pembrokeshire, West Wales. It flows through the Vale of Lampeter to join the Tâf just west of Whitland. The name derives from the Welsh 'marw glais' and signifies a 'stagnant stream'....
(R)
- Afon Cywyn
Tywi catchment
- River TywiRiver TywiWith a total length of the River Towy is the longest river flowing entirely within Wales, and is noted for its sea trout and salmon fishing.The river rises within of the Teifi on the lower slopes of Crug Gynan in the Cambrian Mountains and, flowing through the Towy Forest, forms the border...
(Afon Tywi)- Afon Gwili (R)
- Afon AnnellAfon AnnellAfon Annell is a small river in Carmarthenshire, Wales. Its source is in the Cambrian Mountains and it flows south-westerly via the settlements of Caio and Crugybar until it joins the River Cothi around 2 km east of Llansawel. Some of the waters of the Annell were previously diverted via aqueduct...
(R) - River CothiRiver CothiThe River Cothi is the largest tributary of the River Tywi in south Wales. It is noted for its trout and sea trout fishing and for its beautiful scenery.-Dolaucothi:...
(R) (Afon Cothi)- Afon Gorlech (R)
- Afon TwrchAfon Twrch, CarmarthenshireThe Afon Twrch is a short river in Carmarthenshire, West Wales. It joins the River Cothi at the village of Pumsaint, near to which are the Roman gold mines of Dolaucothi....
(R) - Afon MarlaisAfon Marlais, CarmarthenshireThe Afon Marlais is a right-bank tributary of the River Towy in Carmarthenshire, West Wales. It rises on the slopes of Mynydd Llanfihangel-rhos-y-corn and Mynydd Tre-beddau and flows south-eastwards through Brechfa Forest before reaching the village of Brechfa. After a further kilometre it joins...
(R)
- Afon DulasAfon DulasThe Afon Dulas is a river forming the border between the counties of Gwynedd and Powys in Wales.Prior to local government reorganisation it formed the boundary between Sir Meirionnydd/Merionethshire and Sir Drefaldwyn/Montgomeryshire.-Route:It rises from a source in the hills above Aberllefenni...
(R) - Afon CennenAfon CennenThe Afon Cennen is a river in the county of Carmarthenshire, south Wales. It rises on the northern slopes of the Black Mountain to the east of the summit of Tair Carn Uchaf and flows north to Blaencennen Farm, then westwards past Carreg Cennen Castle, continuing through the village of Trap where it...
(L) - Afon Sawdde (L)
- Afon BranAfon BrânThe Afon Brân is a tributary of the River Towy in mid Wales. Its headwaters rise in Irfon Forest in the northeastern corner of Carmarthenshire as the Cynnant Fawr and Afon Lwynor and the river assumes the name of Afon Brân at their confluence to the north of the village of Cynghordy. Its major...
(L)- Afon Ydw (R)
- Afon Dulais (R)
- Afon BrânAfon BrânThe Afon Brân is a tributary of the River Towy in mid Wales. Its headwaters rise in Irfon Forest in the northeastern corner of Carmarthenshire as the Cynnant Fawr and Afon Lwynor and the river assumes the name of Afon Brân at their confluence to the north of the village of Cynghordy. Its major...
(L)- Cynnant FawrAfon BrânThe Afon Brân is a tributary of the River Towy in mid Wales. Its headwaters rise in Irfon Forest in the northeastern corner of Carmarthenshire as the Cynnant Fawr and Afon Lwynor and the river assumes the name of Afon Brân at their confluence to the north of the village of Cynghordy. Its major...
(Rs)- Cynnant FachAfon BrânThe Afon Brân is a tributary of the River Towy in mid Wales. Its headwaters rise in Irfon Forest in the northeastern corner of Carmarthenshire as the Cynnant Fawr and Afon Lwynor and the river assumes the name of Afon Brân at their confluence to the north of the village of Cynghordy. Its major...
(L)
- Cynnant Fach
- Afon LwynorAfon BrânThe Afon Brân is a tributary of the River Towy in mid Wales. Its headwaters rise in Irfon Forest in the northeastern corner of Carmarthenshire as the Cynnant Fawr and Afon Lwynor and the river assumes the name of Afon Brân at their confluence to the north of the village of Cynghordy. Its major...
(Ls) - Afon Crychan (L)
- Afon GwydderigAfon GwydderigThe River Gwydderig or Afon Gwydderig in Welsh is a tributary of the River Bran . It rises as the Nant Gwydderig on the southern slopes of Mynydd Bwlch-y-groes, about 3 miles North of the small village of Llywel, Powys...
(L)
- Cynnant Fawr
- Afon Gwenlais (R)
- GwenffrwdGwenffrwd, TowyThe Gwenffrwd is a right-bank tributary of the River Towy in northern Carmarthenshire, mid Wales. It rises to the east of Carn Nant-yr-ast and flows in a generally southeasterly direction to its confluence with the Towy, 1 mile to the northwest of the village of Rhandirmwyn. Its only significant...
(R)- Nant Melyn (R)
- Afon Doethie (R)
- Afon Pysgotwr Fawr (R)
- Afon Pysgotwr Fach (R)
- Afon Pysgotwr Fawr (R)
- CamddwrCamddwrThe Camddwr is a significant right-bank tributary of the River Towy in the eastern part of Ceredigion, mid Wales. It rises on the undulating plateau east of Garn Gron and flows in a generally south-southeasterly direction into Llyn Brianne, a reservoir formed by the damming of the upper Towy A...
(R)
Gwendraeth catchment
- River GwendraethRiver GwendraethThe River Gwendraeth is a river in Carmarthenshire in west Wales.It has two almost equal branches that have their confluence in their joint estuary at Carmarthen Bay...
- Gwendraeth Fach (Rs)
- Gwendraeth Fawr (Ls)
Loughor catchment
- River LoughorRiver LoughorThe River Loughor in Carmarthenshire, Wales has its source at an underground lake at the Black Mountain. It flows past settlements like Ammanford and Hendy in Carmarthenshire and Pontarddulais in Swansea. The river divides Carmarthenshire from Swansea for much of its course and it separates Hendy...
(Afon Llwchwr)- Burry Pill (L)
- Afon Lliw (L)
- Afon Llan (L)
- Afon GwiliAfon Gwili (Loughor)The Afon Gwili is a right-bank tributary of the River Loughor in the east of Carmarthenshire, South Wales. It rises near Cross Hands before flowing in a generally southerly direction past the small village of Cwmgwili to join with the Loughor beyond Hendy near Pontarddulais.- References :...
(R) - River AmmanRiver AmmanThe River Amman is a river of south Wales, which joins the River Loughor at Pantyffynnon. The river gives its name to the town of Ammanford and the villages of Pontamman, Glanaman, Brynamman and Rhosaman. Garnant and Betws also lie in the Amman Valley....
(L) - Afon Lash (R)
- Afon MarlasAfon MarlasThe Afon Marlas is a minor right-bank tributary of the River Loughor in eastern Carmarthenshire, West Wales. It rises north of the village of Llandybie and flows southwards through that village and joins the Loughor on the northwestern edge of Ammanford near Aberlash Mill....
(R)
Tawe catchment
- River TaweRiver TaweThe River Tawe is a river in South Wales. It flows in a principally south-westerly direction for some from its source below Moel Feity in the Old Red Sandstone hills of the western Brecon Beacons to the Bristol Channel at Swansea. Its main tributaries are the right bank Upper and Lower Clydach...
- Nant y fendrod (L)
- Lower Clydach River (R)
- Upper Clydach RiverUpper Clydach RiverThe Upper Clydach River runs from a poorly drained area south of Cwmgors village and flows south and southeast through Cwm Gors for about 7km to join the River Tawe at Pontardawe - .-External links:*...
(R)- River Egel (L)
- Afon TwrchAfon TwrchThe Afon Twrch is a river which rises in the Black Mountain in south Wales. It forms the boundary between the counties of Powys and Carmarthenshire and, downstream of Ystradowen, between Powys and Neath Port Talbot county borough.The headwaters arise on the southern slopes of Bannau Sir Gaer and...
(R)- Nant GwysNant GwysThe Nant Gwys is a river flowing off the Black Mountain in Powys, Wales. Its tributaries Gwys Fawr and the Gwys Fach flow south from Banwen Gwyn and Bwlch y Ddeuwynt respectively and join forces to form the Nant Gwys proper which then flows for about 5km / 3mi to its confluence with the Afon Twrch...
(L)- Gwys Fawr (Ls)
- Gwys Fach (Rs)
- Nant Llynfell (R)
- Nant y Llyn (R)
- Nant Gwys
- River GieddRiver GieddThe River Giedd is a river in Powys, Wales and which lies almost wholly within the Brecon Beacons National Park.This river is perhaps unique in the British Isles in that there are in fact two separate rivers sharing the same name and occupying the same valley but which are not hydrologically...
(R)- Nant Cyw (L)
- Nant Ceiliog (L)
- Nant LlechNant LlechThe Nant Llech is a minor river in Powys, Wales and which lies wholly within the Brecon Beacons National Park. The name means 'slab stream', presumably in reference to the sandstones across which it runs...
(L)- Nant Llech Pellaf (L)
- River HaffesRiver HaffesThe Afon Haffes is a river in Powys, Wales and is wholly contained within the Brecon Beacons National Park.Its headwaters rise on the southern and western slopes of Fan Hir at the eastern edge of the Black Mountain and the river joins the River Tawe at Glyntawe after a short and steep...
(R) - Nant Byfre (L)
- Nant y Llyn (R)
Neath catchment
- River NeathRiver NeathRiver Neath is a river in south Wales running south west from its source in the Brecon Beacons National Park to its mouth at Baglan Bay below Briton Ferry on the east side of Swansea Bay.Several minor rivers rise on the southern slopes of Fforest Fawr...
- River ClydachRiver ClydachThe Lower Clydach River is a river in South Wales which rises on the slopes of Mynydd Betws west of Cwmgors and flows for around 10km through Cwm Clydach to its confluence with the River Tawe at Clydach. It runs through the RSPB's Cwm Clydach Nature Reserve just to the north of Clydach. -...
(R) - River DulaisRiver DulaisRiver Dulais is a river of Wales which has its source at Mynydd y Drum. It joins the River Neath after flowing over Aberdulais Falls.-External links:*...
(R) - Melin Cwrt Brook (L)
- Clydach Brook (L)
- Nedd FechanNedd FechanThe Nedd Fechan or 'Little Neath' is a river in the county of Powys, south Wales, Great Britain. It rises on the eastern slopes of Fan Gyhirych in the Fforest Fawr section of the Brecon Beacons National Park and flows south for 12km / 7 mi to join with the Afon Mellte at Pontneddfechan, their...
(Rs)- Afon PyrddinAfon PyrddinThe Afon Pyrddin is a river forming the boundary between the county of Powys and the county borough of Neath Port Talbot in south Wales, Great Britain. It also forms a part of the boundary of the Brecon Beacons National Park...
(R)
- Afon Pyrddin
- Afon Mellte (Ls)
- SychrydSychrydSychryd or Afon Sychryd Starts just below Graig y Llyn and is know localy as the Nant Gwrangon it flows past the village of Rhigos and through Cwm Wyrfa on the edge of the Brecon Beacons National Park and Fforest Fawr Geopark in the county borough of Rhondda Cynon Taf in south Wales...
(L) - Afon HepsteAfon HepsteThe Afon Hepste is a river in Powys, Wales and wholly within the Brecon Beacons National Park.Its headwaters, the Afon y Waun, Nant y Cwrier and Nant Hepste Fechan, rise on the Old Red Sandstone dip-slopes of Fforest Fawr and combine to form the Afon Hepste near the farmstead of Hepste Fechan...
(L) - Afon LliaAfon LliaThe Afon Llia is a short river in Powys, Wales and which is wholly contained within the Brecon Beacons National Park.Several streams draining the eastern slopes of Fan Nedd and the western slopes of Fan Dringarth in the Fforest Fawr section of the national park meet to form the river which then...
(Rs) - Afon DringarthAfon DringarthThe Afon Dringarth is a river in Powys, Wales and wholly contained within the Brecon Beacons National Park. Its headwater streams drain the eastern slopes of Fan Dringarth, the southern slopes of Craig Cerrig-gleisiad and the western slopes of Fan Fawr...
(Ls)
- Sychryd
- River Clydach
Afan catchment
- River AfanRiver AfanThe River Afan is a river in southwest Wales whose river valley formed the territory of the medieval Lords of Afan. The town of Aberavon grew up on the banks of the river, and was later subsumed by the larger centre of population known as Port Talbot...
- Ffrwd Wyllt (L)
- Nant Cwm Wenderi
- Afon Pelenna (R)
- Nant Cregan
- Afon Corrwg (R)
- Afon Corrwg Fechan (R)
Ogmore catchment
- River OgmoreRiver OgmoreThe River Ogmore is a river in South Wales popular with anglers. It runs generally from north to south from the Ogmore Vale and Pentre, past Bridgend and Ogmore...
(Afon Ogwr)- River Ewenny (L)
- Afon AlunAfon Alun (Vale of Glamorgan)The Afon Alun is a river in the Vale of Glamorgan, south Wales. It is a small river, with a length of just 4.5 miles, or 7 kilometres. Its source is just north of Llandow village, where two streams known as the Stembridge Brook and Llandow Brook converge...
(L) - Afon Ewenny Fach (L)
- Nant Canna (L)
- Nant Crymlyn (R)
- Afon Alun
- River LlynfiRiver LlynfiThe River Llynfi, otherwise referred to as the Llynfi River or Afon Llynfi in Welsh , is one of three main tributaries of the River Ogmore or Afon Ogwr....
(R)- Nant y Gadlys (R)
- Nant Cwm-du (L)
- Afon Garw (R)
- Afon Ogwr Fawr (Rs)
- Afon Ogwr Fach (Ls)
- Nant Lechyd (R)
- River Ewenny (L)
Col-huw catchment
- Afon Col-huwAfon Col-huwThe Afon Col-huw is a very short river in Llantwit Major in the Vale of Glamorgan, south Wales....
- Ogney Brook (Rs)
- Hoddnant (Ls)
- Boverton Brook (Ls)
- Llanmaes Brook (Rs)
Thaw catchment
- River ThawRiver ThawThe River Thaw is a river in the Vale of Glamorgan, south Wales. At 20 kilometres/12.4 miles, it is the longest river entirely in the Vale of Glamorgan.-Course:Its source is in the hills just south of the M4 Motorway near Llanharry...
- Kenson River (L)
- River Waycock (Ls)
- Nant Llancarfan (Rs)
- Nant y Stepsau (R)
- Kenson River (L)
Cadoxton catchment
- Cadoxton RiverCadoxton RiverThe Cadoxton River is a short river in the Vale of Glamorgan, South Wales and with a length of about 5 miles/8 kilometres it is one of Wales's shortest rivers.-Course:...
- Bullcroft Brook (Ls)
- Wrinstone Brook (Rs - Only at confluence of Wrinstone Brook and Bullcroft Brook does the river become the Cadoxton)
- East Brook (L)
- Cold Brook, Cadoxton (R)
- Nant yr Argae (Ls)
- Sully Brook (L)
Taff catchment
- River TaffRiver TaffThe River Taff is a large river in Wales. It rises as two rivers in the Brecon Beacons — the Taf Fechan and the Taf Fawr — before joining to form the Taff north of Merthyr Tydfil...
(Afon Tâf)- River ElyRiver ElyThe River Ely is a river in South Wales flowing generally south east, from Tonyrefail to the capital city of Cardiff.-Course of the river:...
(Afon Elai) (R)- Afon ClunAfon ClunThe Afon Clun is a long tributary of the River Ely , in the counties of Cardiff and Rhondda Cynon Taf, South Wales. Its bedrock is predominantly of sandstone...
(L) (Nant Myddlyn in upper reaches)
- Afon Clun
- River RhonddaRiver RhonddaThe River Rhondda is a river in the Rhondda Valley, South Wales which has two major tributaries; the Rhondda Fawr and the Rhondda Fach .- Description :...
(R) (Afon Rhondda)- Rhondda Fawr (Ls)
- Rhondda Fach (Rs)
- River Ritec (Afon Ritec)
- Nant Clydach (R)
- River CynonRiver CynonThe River Cynon is a river in South Wales and is one of the larger tributaries of the River Taff.It arises within Cwm Cadlan in the Brecon Beacons National Park as the Nant Cadlan and is supplemented by a number of small streams arising from springs in the Carboniferous Limestone and Twrch...
(R) (Afon Cynon) - Bargoed Taf (L)
- Nant Morlais
- Taf FechanTaf FechanThe Taf Fechan is a river in the Brecon Beacons in South Wales. It rises just below Pen-y-Fan and joins the Taf Fawr at Cefn-coed-y-cymmer. The river feeds the Pontsticill Reservoir....
(Ls) - Nant Ffrwd (Rs)
- River Ely
Usk catchment
- River UskRiver UskThe River Usk rises on the northern slopes of the Black Mountain of mid-Wales, in the easternmost part of the Brecon Beacons National Park. Initially it flows north into Usk Reservoir, then east by Sennybridge to Brecon before turning southeast to flow by Talybont-on-Usk, Crickhowell and...
(Afon Wysg)- Ebbw RiverEbbw RiverThe Ebbw River is a river in South Wales.The main Ebbw River is formed by the confluence of the two minor Ebbw rivers, Ebbw Fach, and Ebbw Fawr ....
(R) (Afon Ebwy)- Sirhowy River (R)
- River Ebbw Fach (L)
- Afon LlwydAfon LlwydThe Afon Lwyd is a small river in south Wales which flows from its source north of Blaenavon, through Abersychan, Pontypool and Cwmbran before flowing into the River Usk at Caerleon, which subsequently flows into the Bristol Channel in Newport. The name is Welsh, meaning "Grey River".Historically...
(R) - Sôr BrookSor BrookThe Sor Brook is a brook located mostly in Oxfordshire, in the South of England.From its source at Edge Hill in Warwickshire, it flows to the west of Banbury past Broughton Castle and Adderbury to its confluence with the River Cherwell....
(R) - Olway Brook (L)
- Berthin Brook (R)
- Afon Gafenni (L) (River Gavenny)
- River ClydachRiver Clydach, MonmouthshireThe River Clydach is a short, steep and fast-flowing river in Monmouthshire and the county borough of Blaenau Gwent in south Wales. It lies within the Brecon Beacons National Park. It is around in length....
(R) - Grwyne FawrGrwyne FawrThe Grwyne Fawr is a river in the Brecon Beacons National Park in south Wales. A section of it forms the administrative border between Powys and Monmouthshire and also of the historic counties of Brecon and Monmouth. The river and its major tributary the Grwyne Fechan flow into the River Usk at...
(L)- Grwyne Fechan (R)
- RhiangollRhiangollThe Rhiangoll is a river in the Brecon Beacons National Park in southern Powys, south Wales. It rises on the western slopes of Waun Fach in the Black Mountains and drops steeply down to the west into the north-south valley through which the A479 runs between Talgarth and the hamlet of Tretower and...
(L) - Afon Claisfer (R)
- Afon CrawnonAfon CrawnonThe Afon Crawnon is a river in the Brecon Beacons National Park in the county of Powys, south Wales. The headwaters rise on the hills north of Trefil and flow northeast down a valley known as Dyffryn Crawnon for 7km to a confluence with the River Usk just west of Llangynidr...
(R) - CaerfanellCaerfanellThe Caerfanell is a river which rises in the central section of the Brecon Beacons National Park in Powys, Wales. It rises as Blaen Caerfanell on the plateau of Gwaun Cerrig Llwydion and drops steeply down southeastwards into the head of Glyn Collwn before turning east then north-east into Talybont...
(R) - Afon Menasgin (R)
- Afon CynrigAfon CynrigThe Afon Cynrig is a river in Powys, Wales whose headwaters rise in the central Brecon Beacons and flow northwards to join the River Usk at Abercynrig just east of Brecon....
(R) - Afon HondduAfon Honddu (Powys)The Afon Honddu is a river in the county of Powys, mid Wales.It rises on Mynydd Epynt and flows southwards to join the River Usk at Brecon . The river has no major tributaries but acquires numerous streams during its 11-mile course. The valley of the Honddu is followed by the B4520 road which runs...
(L) - Afon Tarell (R)
- Afon YsgirAfon YsgirThe Afon Ysgir is a short river which rises on the southern slopes of Mynydd Epynt in Powys, Wales. The tributaries known as Ysgir Fawr and Ysgir Fechan flow past the hamlets of Pont Rhyd-y-berry and Merthyr Cynog to combine at Pont-faen and continue past the village of Battle to join the River Usk...
(L) - Nant BrânNant Bran*Not to be confused with the Afon Brân in Carmarthenshire.The Nant Brân is a short river which rises on the southern slopes of Mynydd Epynt in Powys, Wales. The word 'brân' means 'crow' in Welsh: the name may therefore allude to the dark colour of its waters.Its upper reaches are within the...
(L) - Afon Cilieni (L)
- Afon SenniAfon SenniThe Afon Senni is a river in Powys, Wales which rises in the Fforest Fawr section of the Brecon Beacons National Park and flows northwards for to a confluence with the River Usk at Sennybridge....
(R) - Afon CraiAfon CraiThe Afon Crai is a river in Powys, Wales rising in the Fforest Fawr section of the Brecon Beacons National Park and flowing north into the River Usk. The headwaters known as Blaen-crai flow north from Bwlch Bryn-rhudd, a col between the Crai valley and the upper Swansea Valley for 2km into the...
(R) - Afon HydferAfon HydferThe Afon Hydfer is a short river in Powys in the west of the Brecon Beacons National Park, south Wales. Its headwaters rise on the northeastern slopes of the Black Mountain as the streams named Trinant, Nant y Cadno, Nant yr Erydr and Crognant joining to flow down Cwm yr Afon on the western edge of...
(R)
- Ebbw River
Wye catchment
- River WyeRiver WyeThe River Wye is the fifth-longest river in the UK and for parts of its length forms part of the border between England and Wales. It is important for nature conservation and recreation.-Description:...
(Afon Gwy)- River TrothyRiver TrothyThe River Trothy is a river which flows through north Monmouthshire, in rural south east Wales.The river rises on Campston Hill, northeast of Abergavenny. It flows southwards until Llanvapley, where it turns east. At Monmouth the river joins into the River Wye, about 0.5 km downstream from the...
(R) - River MonnowRiver MonnowThe River Monnow flows through south-west Herefordshire, England and eastern Monmouthshire, Wales.- Border River :For much of its short length it marks the border between England and Wales before it joins the River Wye at Monmouth. The Wye is also half English from Monmouth until it meets the...
(Afon Mynwy) (R)- River DoreRiver DoreThe River Dore is a tributary of the River Monnow in Herefordshire, England.It rises on Cusop Hill, in the foothills of the Black Mountains, close to the border between England and Wales. It flows for through the villages of Dorstone, Peterchurch, Vowchurch, Abbey Dore and Pontrilas, before...
(L)- Dulas Brook (R)
- Worm Brook (L)
- Afon Honddu (R)
- Olchon Brook (R)
- Escley Brook (L)
- River Dore
- River LuggRiver LuggThe River Lugg , rises near Llangynllo, Powys. It flows through the border town of Presteigne, Wales then through Herefordshire, England, including the town of Leominster, south of which it is met by a tributary, the River Arrow, then to a confluence with the River Wye, which it joins at Mordiford,...
(L) (Afon Llugwy)- River FromeRiver Frome, HerefordshireThe River Frome is a river in Herefordshire, England. It flows through Bromyard, and Bishops Frome. At Covender its tributary, the River Lodon, joins it...
(L) - River KenwaterRiver KenwaterThe River Kenwater is a short tributary of the River Lugg. In fact, it is also an offshoot of that river, separating from it about 2 kilometres north-west of Leominster; it flows through the town and re-joins the Lugg just outside Leominster's east boundary....
- River ArrowRiver Arrow (Wales)The River Arrow is a river in the Welsh Marches, rising in Powys in Wales, then flowing into the English county of Herefordshire.It rises near Gwaunceste Hill, then flows south-east through Newchuch and Michaelchurch-on-Arrow. It forms a short section of the England/Wales boundary, before flowing...
(R)- Cynon Brook
- Gilwern Brook
- Gladestry Brook
- Cynon Brook
- River Frome
- Dulas Brook (R)
- Afon LlynfiAfon Llynfi (Wye)The Afon Llynfi is a short river in the county of Powys, south Wales. A tributary of the River Wye, it runs approximately south to north just to the west of the Black Mountains and partly within the Brecon Beacons National Park. The river rises as a small stream to the west of the village of Bwlch...
(R)- River EnnigAfon Llynfi (Wye)The Afon Llynfi is a short river in the county of Powys, south Wales. A tributary of the River Wye, it runs approximately south to north just to the west of the Black Mountains and partly within the Brecon Beacons National Park. The river rises as a small stream to the west of the village of Bwlch...
(R) - DulasAfon Llynfi (Wye)The Afon Llynfi is a short river in the county of Powys, south Wales. A tributary of the River Wye, it runs approximately south to north just to the west of the Black Mountains and partly within the Brecon Beacons National Park. The river rises as a small stream to the west of the village of Bwlch...
(L)- Triffrwd (L)
- River Ennig
- Bachawy (L)
- Afon Edw (L)
- Duhonw (R)
- Afon IrfonAfon IrfonAfon Irfon is a Site of Special Scientific Interest in Brecknock, Powys, Wales....
(R)- Afon Chwerfri (L)
- DulasDulasDulas may refer to:Saints in the Eastern Orthodox calendar*Dulas *Dulas of CiliciaPlaces*Dulas, Anglesey, a village in Wales**Dulas Bay, nearby*Dulas, Herefordshire, a civil parish in England-See also:...
(L) - Afon Cammarch (L)
- Afon DulasAfon DulasThe Afon Dulas is a river forming the border between the counties of Gwynedd and Powys in Wales.Prior to local government reorganisation it formed the boundary between Sir Meirionnydd/Merionethshire and Sir Drefaldwyn/Montgomeryshire.-Route:It rises from a source in the hills above Aberllefenni...
(R) - Afon Gwesyn (L)
- Dulas Brook (L)
- River IthonRiver IthonThe River Ithon is a major left-bank tributary of the River Wye in Powys, mid Wales. It rises in the broad saddle between the western end of Kerry Hill and the hill of Glog to its west and flows initially southwards to Llanbadarn Fynydd...
(L) (Afon Ieithon)- DulasDulasDulas may refer to:Saints in the Eastern Orthodox calendar*Dulas *Dulas of CiliciaPlaces*Dulas, Anglesey, a village in Wales**Dulas Bay, nearby*Dulas, Herefordshire, a civil parish in England-See also:...
(R) - Clywedog Brook (R)
- Afon Aran (L)
- CamddwrCamddwrThe Camddwr is a significant right-bank tributary of the River Towy in the eastern part of Ceredigion, mid Wales. It rises on the undulating plateau east of Garn Gron and flows in a generally south-southeasterly direction into Llyn Brianne, a reservoir formed by the damming of the upper Towy A...
(L)
- Dulas
- Afon Elan (R)
- Afon Claerwen (R)
- Rhiwnant (R)
- Afon Arban (R)
- Afon Claerddu (R)
- Afon Gwngu (R)
- Afon Claerwen (R)
- Afon MartegRiver MartegThe Afon Marteg is a river in Powys, Wales.It is about 15 km long, flowing roughly south-west to join the Wye at Pont Marteg about 5 km above Rhayader....
(L) - Afon Bidno (L)
- Afon Tarennig (R)
- River Trothy
Severn catchment
With the exception of a small part of the Rea Brook, all tributaries of the Severn downstream of the confluence of the Severn and the Vyrnwy are wholly in England. For details see List of rivers of England.- River SevernRiver SevernThe River Severn is the longest river in Great Britain, at about , but the second longest on the British Isles, behind the River Shannon. It rises at an altitude of on Plynlimon, Ceredigion near Llanidloes, Powys, in the Cambrian Mountains of mid Wales...
(Afon Hafren), Bristol ChannelBristol ChannelThe Bristol Channel is a major inlet in the island of Great Britain, separating South Wales from Devon and Somerset in South West England. It extends from the lower estuary of the River Severn to the North Atlantic Ocean...
(Mor Hafren)- Rea BrookRea BrookThe name Rea Brook can refer to either of two brooks in Shropshire, England.One of the brooks, which eventually becomes the River Rea, is in southern Shropshire. It is to the east of Brown Clee Hill....
(R) (small parts of upper catchment in Wales) - River VyrnwyRiver VyrnwyThe River Vyrnwy is a river which flows through northern Powys, Wales, and Shropshire, England.The river used to be sourced from the many rivers and streams running off the mountains surrounding the Vyrnwy valley. However, since the Lake Vyrnwy dam was built in the 1880s, the river has flowed...
(L) (Afon Efyrnwy) (lowermost section in England)- Afon TanatAfon TanatAfon Tanat is a river in northern Powys, Wales. Its source is close to the Cyrniau Nod mountain, to the north of Lake Vyrnwy. The river flows in a generally east-south-east direction until it joins the River Vyrnwy near Llansantffraid-ym-Mechain. For a short distance prior to its confluence it...
(L) (lowermost section in England)- Cynllaith (L) (part forms the border between Wales and England)
- Afon Ogau
- Afon Iwrch (L)
- Afon RhaeadrRiver RhaeadrThe River Rhaeadr is a river in Wales.It starts at the Pistyll Rhaeadr waterfall a few miles from the village of Llanrhaeadr-ym-Mochnant, where the Afon Disgynfa falls over a 240-foot cliff-face, after which the river is known as the Afon Rhaeadr....
(L) - Afon Eirth (L)
- Cynllaith (L) (part forms the border between Wales and England)
- Afon Cain (L)
- Nant Fyllon (Ls)
- Nant Alan (Rs)
- Afon Banwy (R) (a.k.a. Afon Einion)
- Afon Einion (R)
- Afon Gam (R)
- Afon TwrchAfon TwrchThe Afon Twrch is a river which rises in the Black Mountain in south Wales. It forms the boundary between the counties of Powys and Carmarthenshire and, downstream of Ystradowen, between Powys and Neath Port Talbot county borough.The headwaters arise on the southern slopes of Bannau Sir Gaer and...
(L)
- Afon Tanat
- Maerdy Brook (L)
- New Cut/Guilsfield Brook (L)
- Luggy Brook (L)
- Camlad (R) (partly in England)
- River Rhiw (Afon Rhiw) (L)
- Afon Rhiw (north fork) (Rs)
- Afon Rhiw (south fork)(Ls)
- Llifior Brook (L)
- The MuleThe MuleThe Mule might refer to*Mule , a central character in Isaac Asimov's Foundation series, and the title of a Novella republished as the second half of Foundation and Empire, the second volume of the series....
(R) (Afon Miwl) - Bechan Brook (L)
- Mochdre Brook (R)
- Nant Rhyd-ros lan??
- Afon Carno (L)
- Afon Cerniog (R)
- Afon Cledan (R)
- Afon Trannon (L)
- Afon Cerist (R)
- Colwyn Brook (L)
- Afon Cerist (R)
- Nant Feinion (R)
- Wigdwr Brook (L)
- Afon Clywedog (L)
- Afon Biga (R) (flows into Clywedog ReservoirClywedog reservoirThe Clywedog reservoir is a reservoir in the Welsh county of Powys, located off the B4518 road near the town of Llanidloes.The reservoir was formed by damming the Afon Clywedog, a tributary of the River Severn. Its concrete buttress dam is the tallest concrete dam in the United Kingdom, with a...
) - Afon LlwydAfon LlwydThe Afon Lwyd is a small river in south Wales which flows from its source north of Blaenavon, through Abersychan, Pontypool and Cwmbran before flowing into the River Usk at Caerleon, which subsequently flows into the Bristol Channel in Newport. The name is Welsh, meaning "Grey River".Historically...
(R) (flows into Clywedog ReservoirClywedog reservoirThe Clywedog reservoir is a reservoir in the Welsh county of Powys, located off the B4518 road near the town of Llanidloes.The reservoir was formed by damming the Afon Clywedog, a tributary of the River Severn. Its concrete buttress dam is the tallest concrete dam in the United Kingdom, with a...
)
- Afon Biga (R) (flows into Clywedog Reservoir
- Afon DulasAfon DulasThe Afon Dulas is a river forming the border between the counties of Gwynedd and Powys in Wales.Prior to local government reorganisation it formed the boundary between Sir Meirionnydd/Merionethshire and Sir Drefaldwyn/Montgomeryshire.-Route:It rises from a source in the hills above Aberllefenni...
(R)- Afon Brochan (L)
- Nant Cydros (R)
- Rhydyclwydau Brook (R)
- Rea Brook
Longest rivers in Wales
This is a table of the longest rivers in Wales.Rivers only partly in Wales are included in this table in italics. Note that river lengths given by different authorities vary due to the different ways in which the measurement is made or indeed estimated. That rivers are partly fractal in nature accounts for some variation and lengths can also vary slightly over time as meanders expand or are cut off where rivers run through broad flood-plains.
| River | Length (miles) | (km) | |
|---|---|---|---|
| 1 | River Severn River Severn The River Severn is the longest river in Great Britain, at about , but the second longest on the British Isles, behind the River Shannon. It rises at an altitude of on Plynlimon, Ceredigion near Llanidloes, Powys, in the Cambrian Mountains of mid Wales... | 220 | 354 |
| 2 | River Wye River Wye The River Wye is the fifth-longest river in the UK and for parts of its length forms part of the border between England and Wales. It is important for nature conservation and recreation.-Description:... | 135 | 215 |
| 3 | River Teme River Teme The River Teme rises in Mid Wales, south of Newtown in Powys, and flows through Knighton where it crosses the border into England down to Ludlow in Shropshire, then to the north of Tenbury Wells on the Shropshire/Worcestershire border there, on its way to join the River Severn south of Worcester... | 81 | 121 |
| 4 | River Dee River Dee, Wales The River Dee is a long river in the United Kingdom. It travels through Wales and England and also forms part of the border between the two countries.... | 70 | 112 |
| 5 | River Towy | 68 | 109 |
| 6 | River Usk River Usk The River Usk rises on the northern slopes of the Black Mountain of mid-Wales, in the easternmost part of the Brecon Beacons National Park. Initially it flows north into Usk Reservoir, then east by Sennybridge to Brecon before turning southeast to flow by Talybont-on-Usk, Crickhowell and... | 56 | 90 |
| 7 | River Teifi River Teifi The River Teifi forms the boundary between the counties of Ceredigion and Carmarthenshire in south-west Wales for most of its 75 mile length, flowing into the sea below the town of Cardigan. The catchment of the river is estimated to be 1,008 square kilometres yielding an average flow at Glan... | 50 | 80 |
| 8 | River Taff River Taff The River Taff is a large river in Wales. It rises as two rivers in the Brecon Beacons — the Taf Fechan and the Taf Fawr — before joining to form the Taff north of Merthyr Tydfil... | 40 | 64 |
See also
- List of rivers of the United Kingdom
- List of rivers in England
- List of rivers in Ireland
- List of rivers of the Isle of Man
- List of rivers in Scotland
- Main riverMain riverMain rivers are a statutory type of watercourse in England and Wales, usually larger streams and rivers, but also include some smaller watercourses. A main river is defined as a watercourse marked as such on a main river map, and can include any structure or appliance for controlling or regulating...