Cwm Idwal
Encyclopedia
Cwm Idwal is a hanging valley in the Glyderau
range of mountains in northern Snowdonia
, the national park in the mountainous region of North Wales
. Its main interest is to hill walkers and rock climbers
, but it is also of interest to geologists and naturalists, given its combination of altitude (relatively high in UK terms), aspect
(north-facing) and terrain
(mountainous and rocky). In a 2005 poll
conducted by Radio Times
, Cwm Idwal was ranked the 7th greatest natural wonder in Britain.
Cwm Idwal is a spectacular product of glaciation, surrounded by high crags, scree
s, moraine
s and rounded rocks, with a lake on its floor (Llyn Idwal
). Cwm Idwal comprises volcanic
and sedimentary rock
which was laid down in a shallow Ordovician
sea, and later folded to give rise to the distinctive trough-shaped arrangement of strata
known today as the Idwal Syncline
. This fold in the rock is visible today, thanks to the layering of the sedimentary rocks. The area was then eroded by glacial action to form the classic semicircular valley.
and some alpine saxifrage
s, such as tufted saxifrage
(Saxifraga cespitosa) and Saxifraga nivalis
, can be found. It is also a home of the Snowdon lily
, a plant which can only be found in the UK
on Snowdon
and its surroundings. Evan Roberts
, the renowned botanist and explorer from Capel Curig
, did probably as much as any other (self taught) botanist to document the area. The Snowdonia hawkweed, Hieracium snowdoniense is only known to occur in Cwm Idwal.
The Idwal slabs and the cliffs around the head of Cwm Idwal are a popular area for rock climbing; the Idwal Slabs (on the eastern side of the Cwm) in particular are popular with inexperienced climbers learning their skills. The Devil's Kitchen has some excellent ice climbing
during the winter. It is also popular for hill walking and scrambling
, given its proximity to Tryfan
and Glyder Fach
and Glyder Fawr
and their profusion of rocky ridges.
In the mid to late 1950s and into the 1960s, this was the reunion excursion camp site of the first ascenders of Mount Everest
and Kangchenjunga
, held at Pen-y-Gwryd
, many of whom were keen geologist
s and botanists.
Glyderau
The Glyderau are a mountain group in Snowdonia, North Wales. The name derives from the highest peaks in the range, Glyder Fawr and Glyder Fach....
range of mountains in northern Snowdonia
Snowdonia
Snowdonia is a region in north Wales and a national park of in area. It was the first to be designated of the three National Parks in Wales, in 1951.-Name and extent:...
, the national park in the mountainous region of North Wales
North Wales
North Wales is the northernmost unofficial region of Wales. It is bordered to the south by the counties of Ceredigion and Powys in Mid Wales and to the east by the counties of Shropshire in the West Midlands and Cheshire in North West England...
. Its main interest is to hill walkers and rock climbers
Rock climbing
Rock climbing also lightly called 'The Gravity Game', is a sport in which participants climb up, down or across natural rock formations or artificial rock walls. The goal is to reach the summit of a formation or the endpoint of a pre-defined route without falling...
, but it is also of interest to geologists and naturalists, given its combination of altitude (relatively high in UK terms), aspect
Aspect (geography)
In physical geography, aspect generally refers to the horizontal direction to which a mountain slope faces. For example, a slope on the eastern edge of the Rockies toward the Great Plains is described as having an easterly aspect...
(north-facing) and terrain
Terrain
Terrain, or land relief, is the vertical and horizontal dimension of land surface. When relief is described underwater, the term bathymetry is used...
(mountainous and rocky). In a 2005 poll
Opinion poll
An opinion poll, sometimes simply referred to as a poll is a survey of public opinion from a particular sample. Opinion polls are usually designed to represent the opinions of a population by conducting a series of questions and then extrapolating generalities in ratio or within confidence...
conducted by Radio Times
Radio Times
Radio Times is a UK weekly television and radio programme listings magazine, owned by the BBC. It has been published since 1923 by BBC Magazines, which also provides an on-line listings service under the same title...
, Cwm Idwal was ranked the 7th greatest natural wonder in Britain.
Geology
Scree
Scree, also called talus, is a term given to an accumulation of broken rock fragments at the base of crags, mountain cliffs, or valley shoulders. Landforms associated with these materials are sometimes called scree slopes or talus piles...
s, moraine
Moraine
A moraine is any glacially formed accumulation of unconsolidated glacial debris which can occur in currently glaciated and formerly glaciated regions, such as those areas acted upon by a past glacial maximum. This debris may have been plucked off a valley floor as a glacier advanced or it may have...
s and rounded rocks, with a lake on its floor (Llyn Idwal
Llyn Idwal
Llyn Idwal is a small lake that lies within Cwm Idwal in the Glyderau mountains of Snowdonia.It is named after a son of Owain Gwynedd, one of the ancient Princes of Wales, legend stating that the unfortunate offspring was murdered by being drowned in the lake.A number of small streams flow into...
). Cwm Idwal comprises volcanic
Volcanic rock
Volcanic rock is a rock formed from magma erupted from a volcano. In other words, it is an igneous rock of volcanic origin...
and sedimentary rock
Sedimentary rock
Sedimentary rock are types of rock that are formed by the deposition of material at the Earth's surface and within bodies of water. Sedimentation is the collective name for processes that cause mineral and/or organic particles to settle and accumulate or minerals to precipitate from a solution....
which was laid down in a shallow Ordovician
Ordovician
The Ordovician is a geologic period and system, the second of six of the Paleozoic Era, and covers the time between 488.3±1.7 to 443.7±1.5 million years ago . It follows the Cambrian Period and is followed by the Silurian Period...
sea, and later folded to give rise to the distinctive trough-shaped arrangement of strata
Stratum
In geology and related fields, a stratum is a layer of sedimentary rock or soil with internally consistent characteristics that distinguish it from other layers...
known today as the Idwal Syncline
Syncline
In structural geology, a syncline is a fold, with younger layers closer to the center of the structure. A synclinorium is a large syncline with superimposed smaller folds. Synclines are typically a downward fold, termed a synformal syncline In structural geology, a syncline is a fold, with younger...
. This fold in the rock is visible today, thanks to the layering of the sedimentary rocks. The area was then eroded by glacial action to form the classic semicircular valley.
Botany
Given its elevation and north-facing aspect, Cwm Idwal is the most southerly place in Britain where Arctic plants such as moss campionMoss campion
Silene acaulis, moss campion, is a small mountain-dwelling wildflower that is common all over the high arctic and the higher mountains of Eurasia and North America, .It is densely tufted, forming domed cushions composed of long shoots with four or five small green...
and some alpine saxifrage
Saxifrage
Saxifraga is the largest genus in the family Saxifragaceae, containing about 440 species of Holarctic perennial plants, known as saxifrages. The Latin word saxifraga means literally "stone-breaker", from Latin + ...
s, such as tufted saxifrage
Tufted Saxifrage
The tufted saxifrage is a flower common to many arctic heights. It appears further south in mountainous areas of the Alps, Norway, Iceland, Siberia, and Alaska....
(Saxifraga cespitosa) and Saxifraga nivalis
Saxifraga nivalis
Saxifraga nivalis is a species of saxifrage. It is commonly called Snow Saxifrage or "alpine saxifrage".Found on irrigated rocks or open vegetation in shaded sites, often on mountain ledges and crags with base rich substratum. This species is not very tolerant of competition and so is found in...
, can be found. It is also a home of the Snowdon lily
Lloydia serotina
Lloydia serotina is an arctic-alpine flowering plant of the lily family. It is the only member of the genus Lloydia to live outside central and eastern Asia, and is widespread across western North America, from Alaska to New Mexico, and in Europe is found in the Alps and Carpathians, as well as in...
, a plant which can only be found in the UK
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
on Snowdon
Snowdon
Snowdon is the highest mountain in Wales, at an altitude of above sea level, and the highest point in the British Isles outside Scotland. It is located in Snowdonia National Park in Gwynedd, and has been described as "probably the busiest mountain in Britain"...
and its surroundings. Evan Roberts
Evan Roberts (botanist)
Evan Roberts MBE, M.Sc., .Evan Roberts was an internationally known and recognised botanist who lived and worked all his life in Capel Curig , in Snowdonia, Gwynedd, North Wales....
, the renowned botanist and explorer from Capel Curig
Capel Curig
Capel Curig is a village and community in Conwy County Borough, in Wales. It lies in the heart of Snowdonia, on the River Llugwy, and has a population of 226...
, did probably as much as any other (self taught) botanist to document the area. The Snowdonia hawkweed, Hieracium snowdoniense is only known to occur in Cwm Idwal.
Mountaineering
Ice climbing
Ice climbing, as the term indicates, is the activity of ascending inclined ice formations. Usually, ice climbing refers to roped and protected climbing of features such as icefalls, frozen waterfalls, and cliffs and rock slabs covered with ice refrozen from flows of water. For the purposes of...
during the winter. It is also popular for hill walking and scrambling
Scrambling
Scrambling is a method of ascending rocky faces and ridges. It is an ambiguous term that lies somewhere between hillwalking and rock climbing. It is often distinguished from hillwalking by defining a scramble as a route where hands must be used in the ascent...
, given its proximity to Tryfan
Tryfan
Tryfan is a mountain in Snowdonia, Wales, forming part of the Glyderau group. It is one of the most recognisable peaks in the region, having a classic pointed shape with rugged crags. At 3,010 feet above sea level it is the fifteenth highest mountain in Wales...
and Glyder Fach
Glyder Fach
Glyder Fach is a mountain in Snowdonia, north-west Wales, and is the second highest of the Glyderau and the sixth highest in Wales.Routes to the summit lead from Tryfan and Bristly Ridge to the north, via Glyder Fawr from Pen-y-Pass to the south, and along the Glyder ridge to the east, towards...
and Glyder Fawr
Glyder Fawr
' is a mountain in Snowdonia, Wales, the highest in the Glyderau. At just over 1,000m, it is the fifth highest mountain in Wales.It lies on the ridge between and , and has views to the north, across the Ogwen Valley, of and the , and views south to the Snowdon Horseshoe. The summit is very rocky,...
and their profusion of rocky ridges.
In the mid to late 1950s and into the 1960s, this was the reunion excursion camp site of the first ascenders of Mount Everest
Mount Everest
Mount Everest is the world's highest mountain, with a peak at above sea level. It is located in the Mahalangur section of the Himalayas. The international boundary runs across the precise summit point...
and Kangchenjunga
Kangchenjunga
Kangchenjunga is the third highest mountain of the world with an elevation of and located along the India-Nepal border in the Himalayas.Kangchenjunga is also the name of the section of the Himalayas and means "The Five Treasures of Snows", as it contains five peaks, four of them over...
, held at Pen-y-Gwryd
Pen-y-Gwryd
Pen-y-Gwryd is a pass at the head of Nantygwryd and Nant Cynnyd rivers in Gwynedd, North Wales and a quarter of a mile from the boundary with Conwy in northern Snowdonia, close to the foot of Snowdon...
, many of whom were keen geologist
Geologist
A geologist is a scientist who studies the solid and liquid matter that constitutes the Earth as well as the processes and history that has shaped it. Geologists usually engage in studying geology. Geologists, studying more of an applied science than a theoretical one, must approach Geology using...
s and botanists.