The Afon Honddu is a river in the county of Powys

Powys

Powys is a local-government county and preserved county in Wales.-Geography:Powys covers the historic counties of Montgomeryshire and Radnorshire, most of Brecknockshire , and a small part of Denbighshire — an area of 5,179 km², making it the largest county in Wales by land area.It is...

, mid Wales

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...

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It rises on Mynydd Epynt

Mynydd Epynt

Mynydd Epynt is an upland area of Mid Wales within the county of Powys, Wales. It is bounded to the south by the upper section of the valley of the River Usk, to the north by that of the Afon Irfon and to the east by the valley of the River Wye. Its western boundary is less distinct but lies...

 and flows southwards to join the 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...

 at Brecon

Brecon

Brecon is a long-established market town and community in southern Powys, Mid Wales, with a population of 7,901. It was the county town of the historic county of Brecknockshire; although its role as such was eclipsed with the formation of Powys, it remains an important local centre...

 . 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 north from Brecon to Builth Wells

Builth Wells

Builth Wells is a town in the county of Powys, within the historic boundaries of Brecknockshire, mid Wales, lying at the confluence of the River Wye and the River Irfon, in the Welsh of the Wye Valley. It has a population of 2,352....

. The road serves the hamlets of Upper Chapel

Upper Chapel, Powys

Upper Chapel is a hamlet in the southern part of the county of Powys in mid Wales. It lies on the B4520, Brecon to Builth Wells road in the valley of the Afon Honddu. The south-flowing Honddu cuts deeply into the uplands of Mynydd Epynt north of Brecon...

, Lower Chapel, Pwllgloyw and Llandefaelog each of which, Pwllgloyw apart, sit at bridging points of the Honddu.

Brecon Castle, now a hotel, sits at the lowermost crossing of the river at its confluence with the Usk. For the last 1.5 miles (2.4 km) of its course, it lies partly or wholly within Brecon Beacons National Park and Fforest Fawr Geopark

Fforest Fawr Geopark

Fforest Fawr Geopark was the first Geopark to be designated in Wales having gained membership of both the European Geoparks Network and the UNESCO-assisted Global Network of National Geoparks in October 2005. The Geopark aims to promote and support sustainable tourism and other opportunities to...

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