The Afon Crai is a river in 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...

, 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...

 rising in the Fforest Fawr

Fforest Fawr

Fforest Fawr is the name given to an extensive upland area in the county of Powys, Wales. Formerly known as the 'Great Forest of Brecknock' in English, it was a royal hunting area for several centuries but is now used primarily for sheep grazing, forestry, water catchment and recreation...

 section of the Brecon Beacons National Park and flowing north into 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...

. The headwaters known as Blaen-crai flow north from Bwlch Bryn-rhudd, a col

Mountain pass

A mountain pass is a route through a mountain range or over a ridge. If following the lowest possible route, a pass is locally the highest point on that route...

 between the Crai valley and the upper Swansea Valley

Swansea Valley

The Swansea Valley , one of the South Wales Valleys is the name often given to the valley of the River Tawe area in South Wales, UK. It reaches southwest and south from the Brecon Beacons National Park down to the city of Swansea. Today, administration of the area is divided between the City and...

 for 2km into the Cray Reservoir

Cray reservoir

Cray Reservoir is a storage reservoir located in the Brecon Beacons National Park for the water supply to the city of Swansea in South Wales and was built between 1898 and 1906 by Swansea Corporation....

. The river emerges from below the dam to flow a further 8km through the dispersed settlement of Crai

Crai

Crai is a hamlet in the Brecon Beacons National Park in the county of Powys, south Wales. It gives its name to the community within which are the hamlet of Felin-Crai and a large number of dispersed farms around the valley of the Afon Crai. The river is dammed 2km / 1.5mi southwest of the village...

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In common with other tributaries of the River Usk and the Usk itself, the Afon Crai is designated as a special area of conservation

Special Area of Conservation

A Special Area of Conservation is defined in the European Union's Habitats Directive , also known as the Directive on the Conservation of Natural Habitats and of Wild Fauna and Flora...

 for its three species of lamprey

Lamprey

Lampreys are a family of jawless fish, whose adults are characterized by a toothed, funnel-like sucking mouth. Translated from an admixture of Latin and Greek, lamprey means stone lickers...

, twaite shad, European bullhead

European bullhead

The bullhead is a freshwater fish that is widely distributed in Europe, mainly in rivers. It is a member of the Cottidae family, a type of sculpin...

, Atlantic salmon

Atlantic salmon

The Atlantic salmon is a species of fish in the family Salmonidae, which is found in the northern Atlantic Ocean and in rivers that flow into the north Atlantic and the north Pacific....

 and otter

Otter

The Otters are twelve species of semi-aquatic mammals which feed on fish and shellfish, and also other invertebrates, amphibians, birds and small mammals....

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