This is a list of rivers of Wales, organised

geographical Geography (from Ancient Greek ; combining 'Earth' and 'write', literally 'Earth writing') is the study of the lands, features, inhabitants, and phenomena of Earth. Geography is an all-encompassing discipline that seeks an understanding o ...

ly. It is taken anti-clockwise from the

Dee Estuary The 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-mile (8 km) 'canalised' section and the river soon swells to be several miles wide forming t ...

to the M48 Bridge that separates the estuary of the

River Wye The River Wye (; ) is the Longest rivers of the United Kingdom, fourth-longest river in the UK, stretching some from its source on Plynlimon in mid Wales to the Severn Estuary. The lower reaches of the river forms part of Wales-England bor ...

from the

River Severn The River Severn (, ), at long, is the longest river in Great Britain. It is also the river with the most voluminous flow of water by far in all of England and Wales, with an average flow rate of at Apperley, Gloucestershire. It rises in t ...

Tributaries A tributary, or an ''affluent'', is a stream or river that flows into a larger stream ('' main stem'' or ''"parent"''), river, or a lake. A tributary does not flow directly into a sea or ocean. Tributaries, and the main stem river into which the ...

are listed down the page in an upstream direction, starting with those closest to the sea. The

main stem In hydrology, a main stem or mainstem (also known as a trunk) is "the primary downstream segment of a river, as contrasted to its tributaries". The mainstem extends all the way from one specific headwater to the outlet of the river, although t ...

(or principal) river of a catchment is given, left-bank tributaries are indicated by (L), and 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 is formed by the confluence of two differently named rivers, these are labelled as (Ls) and (Rs) for the left and right forks. A prime example is the formation of the

River Taff The River Taff () is a river in Wales. It rises in the Brecon Beacons as two rivers, the Taf Fechan ("little Taff") and the Taf Fawr ("great Taff") before becoming one just north of Merthyr Tydfil. At Cardiff, it empties into the Bristol Chan ...

from the Taf Fawr and the Taf Fechan at Cefn Coed-y-cymmer. The list includes more or less every watercourse named on

Ordnance Survey The Ordnance Survey (OS) is the national mapping agency for Great Britain. The agency's name indicates its original military purpose (see Artillery, ordnance and surveying), which was to map Scotland in the wake of the Jacobite rising of ...

mapping and thus many of the

main river The Main () is the longest tributary of the Rhine, one of the major European rivers. It rises as the White Main in the Fichtel Mountains of northeastern Bavaria and flows west through central Germany for to meet the Rhine below Rüsselsheim, ...

s of

Wales Wales ( ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by the Irish Sea to the north and west, England to the England–Wales border, east, the Bristol Channel to the south, and the Celtic ...

(as defined by

Natural Resources Wales Natural Resources Wales () is a Welsh Government sponsored body, which became operational from 1 April 2013, when it took over the management of the natural resources of Wales. It was formed from a merger of the Countryside Council for Wales, E ...

). 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).

Mainland rivers flowing into Liverpool Bay

''From

Garth Pier Garth Pier (; also known as Bangor Pier) is a Grade II listed structure in Bangor, Wales. At in length, it is the second-longest pier in Wales, and the ninth longest in the British Isles. Construction Designed by J.J. Webster of Westminster, ...

Bangor, Gwynedd Bangor (; ) is a City status in the United Kingdom, cathedral city and Community (Wales), community in Gwynedd, north Wales. It is the oldest city in Wales. Historic counties of Wales, Historically part of Caernarfonshire, the community had a ...

Dee catchment

River Dee, Wales The River Dee (, ) flows through North Wales and Cheshire, England. The majority of the river is located in Wales, with the stretch between Aldford and Saltney within England and two other sections forming the border between the two countries ...

(Afon Dyfrdwy) ** Nant-y-fflint (L) (flows into

) ** Wepre Brook (L) (flows into Dee Estuary) **

Aldford Brook Aldford 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. Rising at an altitude of around 78m, just to the south west of Malpas the stream flows generally north past ...

(R) (wholly in England) **

River Alyn The River Alyn () is a tributary of the River Dee in north-east Wales. It rises at the southern end of the Clwydian hills and the Alyn Valley forms part of the Clwydian Range and Dee Valley Area of Outstanding Natural Beauty. The main tow ...

(L) (Afon Alun / River Alun) ***

River Cegidog The 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 Wrexham County Borough () is a Principal areas of Wa ...

(R) (Afon Cegidog) **** Nant-y-Ffrith (R) ***

River Terrig The 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.'' Cambridge County Ge ...

(R) (Afon Terrig) **

Worthenbury Brook Willington Worthenbury () is a Community (Wales), community in Wrexham County Borough, Wales, and is situated near the England–Wales border. It has an area of 2,146 hectares and a population of 730 (United Kingdom Census 2001, 2001 census), i ...

(R) *** Emral Brook (Ls) ***

Wych Brook The Wych Brook, Worthenbury Brook and Red Brook, formerly known as the River Elfe, is a tributary of the River Dee in England and Wales, forming part of both the historic and present-day border between the two countries. The stream forms part ...

(Rs) (formerly known as the "River Elfe") **** Red Brook (L) **

River Clywedog The River Clywedog is a river in Wrexham County Borough, Wales. Its uses have been watering crops, powering industrial machinery but is now used as walking trails or geography trips. The river originates to the west of Wrexham, and joins the ...

(L) (Afon Clywedog) ***

River Gwenfro The River Gwenfro () is a small river in Wrexham County Borough, north Wales. It is a tributary of the Clywedog.''Rand McNally encyclopedia of world rivers'', 1980, p.167 The name Gwenfro is possibly derived from the Welsh language words ''gwen ...

(L) (Afon Gwenfro) ***

Glanyrafon Brook Aberystwyth (; ) is a university and seaside town and a community in Ceredigion, Wales. It is the largest town in Ceredigion and from Aberaeron, the county's other administrative centre. In 2021, the population of the town was 14,640. Locat ...

(R) **** Black Brook (R) (Afon Ddu) **

Shell Brook Shell River, formerly Shell Brook, is a river in the north-central region of the Canadian province of Saskatchewan. The river begins at Big Shell Lake and travels in an easterly direction and flows into the Sturgeon River north of the city o ...

(R) **

River Ceiriog The River Ceiriog () is an long river in north east Wales, whose name may derive from a term meaning "favoured one". It is a tributary of the River Dee. It rises at an altitude of around on the south east slopes of Moel Fferna in the Berwyn ...

(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 Eitha (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 Tryweryn Afon Tryweryn is a river in the north of Wales which starts at Llyn Tryweryn in the Snowdonia National Park Snowdonia, or Eryri (), is a mountainous region and National parks of the United Kingdom, national park in North Wales. It contain ...

(L) (River Tryweryn) *** Afon Mynach (Dee) (L) *** Afon Hesgyn (L) *** Afon Gelyn (L) (flows into

Llyn Celyn Llyn Celyn () is a reservoir constructed between 1960 and 1965 including the highly controversial Tryweryn flooding in the valley of the River Afon Tryweryn, Tryweryn in Gwynedd, Wales. This included the forcible removal of the Capel Celyn vil ...

) *** Nant Aberderfel (R) (flows into Llyn Celyn) ** Afon Llafar (L) (flows into

Bala Lake Bala Lake, or (), is a large freshwater glacial lake in Gwynedd, Wales. The River Dee, which has its source on the slopes of Dduallt in the mountains of Snowdonia, feeds the long by wide lake. It was the largest natural body of water in ...

) **

Afon Twrch The Afon Twrch is a river which rises in the Black Mountain in south Wales. It forms the boundary between Powys and Carmarthenshire and, downstream of Ystradowen, between Powys and Neath Port Talbot. Name The name derives from Welsh '' afon'' ...

(R) ** Afon Lliw (L)

Clwyd catchment

River Clwyd The River Clwyd ( ; , ) is a river in Wales that rises in the Clocaenog Forest () northwest of Corwen. Its total length is . It flows due south until, at Melin-y-wig, it veers north-eastwards due to the Vale of Clwyd Fault and passes throu ...

(Afon Clwyd) ** River Gele (L) (Afon Gele) **

River Elwy The River Elwy () is a river in Wales forming a tributary to the River Clwyd. Though the source of the river may be on the northern flank of Moel Seisiog, south-east of Llanrwst, the river only receives the name Elwy at the village of Llanger ...

(L) (Afon Elwy; also known as Afon Cledwen above the village of Llangernyw) *** (R) *** River Aled (R) *** Afon Gallen (Ls) ** River Wheeler (R) (Afon Chwiler) ** (R) **

(L) (Afon Clywedog; not to be confused with the Dee tributary of the same name)

Conwy catchment

River Conwy The River Conwy (; ) is a river in north Wales. From its source to its discharge in Conwy Bay it is long and drains an area of 678 square km. "Conwy" was formerly anglicised as "Conway." The name 'Conwy' derives from the old Welsh words ''c ...

(Afon Conwy) ** Afon Gyffin (L) ** Afon Roe (L) (known as Afon Tafolog in upper reaches) **

Afon Dulyn is the outflow from Llyn Dulyn, a lake in the Carneddau mountains in north-west Wales. It is a tributary of the river Conwy. Just below Afon Dulyn the river is joined by Afon Melynllyn, a small river flowing from neighbouring Llyn Melynlly ...

(L) *** Afon Ddu (L) *** Afon Garreg-wen (L) *** Ffrwd Cerriguniawn (L) *** Afon Melynllyn (R) ** Afon Porth-llwyd (L) *** Afon Eigiau ** Afon Ddu (L) ** Afon Crafnant (L) *** Afon Geirionydd (R) ** Afon Gallt y Gwg (R) ** Nant y Goron (R) ** Afon Llugwy (L) ***

Nantygwryd Dyffryn Mymbyr is a valley in Snowdonia, in north-west Wales, approximately in length, and leading up from Capel Curig to the Pen-y-Gwryd hotel. The river Nantygwryd, originally called Y Mymbyr in Llywelyn the Great's charter of 1198, starts ...

(R) **

Afon Lledr is a river in north-west Wales and the second major tributary of the River Conwy. It is about 10 miles or 16 km long, and flows in a generally easterly direction. The has its source on the eastern slopes of , which lies about 3 km ...

(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 Ddu ** Afon Glan-sais (L) ** Afon Maes-y-bryn (R) ** Afon Llanfairfechan,

Llanfairfechan ; ) is a town and community in the Conwy County Borough, Wales. It is known as a seaside resort and had a population at the 2001 Census of 3,755, reducing to 3,637 at the 2011 Census. The history of the area dates back to at least Roman time ...

Afon Dulas The Afon Dulas, or North Dulas, is a river forming the border between Merionethshire/Gwynedd and Montgomeryshire/Powys in Wales. Another river called Afon Dulas joins the Dyfi from the south, upstream of its confluence with the North Dulas: loca ...

Llanddulas Llanddulas is a village in Conwy county borough, Wales, midway between Old Colwyn and Abergele and next to the North Wales Expressway in the community of Llanddulas and Rhyd-y-Foel. The village lies beneath the limestone hill of Cefn-yr-Og ...

Afon Colwyn The Afon Colwyn () is a small river in Gwynedd, north-west Wales, a tributary of the Afon Glaslyn. It has its source on the south-western flank of Yr Aran, near Snowdon. It first flows west to cross the A4085 Caernarfon to Beddgelert road ...

Old Colwyn Old Colwyn (, formerly ''Colwyn'' bilingually) is a large village just to the east of Colwyn Bay, in Conwy County Borough, Wales. Prior to local government reorganisation in April 1974 it was part of the Municipal Borough of Colwyn Bay, but th ...

Aber catchment

* Afon Aber ** Afon Anafon (Rs) ** Afon Rhaeadr Fawr (Ls) *** Afon Rhaeadr Bach (Ls) **** Afon Gam (L) *** Afon Goch (Rs)

Ogwen catchment

* Afon Ogwen ** Afon Caseg (R) *** Afon Llafar (L) *** Afon Denau (flows into Llyn Ogwen) **** Nant Gwern y Gof (L) *** Afon Lloer (flows into Llyn Ogwen)

Cegin catchment

River Cegin The Afon Cegin (''River Cegin'' in English) is a small river draining parts of North Wales and discharging to the Menai Strait at Porth Penrhyn. Its name means ''Kitchen River'' in English. Course The headwaters include two sites near Pentir. ...

(Afon Cegin)

Adda catchment

* River Adda (Afon Adda)

Isle of
Anglesey Anglesey ( ; ) is an island off the north-west coast of Wales. It forms the bulk of the Principal areas of Wales, county known as the Isle of Anglesey, which also includes Holy Island, Anglesey, Holy Island () and some islets and Skerry, sker ...
rivers

Anticlockwise from

Menai Bridge Menai Bridge (; usually referred to colloquially as ''Y Borth'') is a town and community on the Isle of Anglesey in north-west Wales. It overlooks the Menai Strait and lies by the Menai Suspension Bridge, built in 1826 by Thomas Telford, j ...

/ Porthaethwy

Minor coastal catchments

* Afon Cadnant (River Cadnant) * Nant Meigan * Lleiniog * Afon Nodwydd *

Afon y Marchogion This is a list of rivers of Wales, organised geographically. It is taken anti-clockwise from the Dee Estuary to the M48 Bridge that separates the estuary of the River Wye from the River Severn. Tributaries are listed down the page in an upstrea ...

* Afon Lligwy * Nant Perfedd * Afon Goch (Dulas) * Nant y Beddyw * Afon Bryn Gwyn * Afon Goch (Amlwch) * Afon Wygyr * Gwter Fudr *

Afon Alaw The Afon Alaw () is a river on Anglesey (Welsh language, Welsh: Ynys Môn) in Wales which rises near Llanerch-y-medd and flows northwards into the reservoir of Llyn Alaw. Below the dam it then flows southwestwards to the island's west coast near ...

(River Alaw)

Crigyll catchment

* Afon Crigyll ** Afon Caradog (L)

Ffraw catchment

Afon Ffraw The Afon Ffraw is a short river on the Isle of Anglesey, Wales. It arises at Llyn Coron and flows southwest for two miles along the northwestern margin of Twyn Aberffraw ('Aberffraw dunes') via the village of Aberffraw to Aberffraw Bay on the is ...

** Afon Frechwen (L) ** Afon Gwna (flows into Llyn Coron)

Cefni catchment

Afon Cefni Afon Cefni is one of the major rivers on the island of Anglesey, Wales. It is long. Its source is near to the village of Capel Coch, before flowing through Bodffordd and into Llyn Cefni in the centre of the island. It continues to run south ...

(River Cefni) ** Afon Newydd (L) ** Afon Ceint (L) ** Afon Erddreiniog (L) (flows into Cefni Reservoir)

Braint (i) catchment

The Afon Braint bifurcates near

Llanfairpwllgwyngyll Llanfairpwllgwyngyll or Llanfair Pwllgwyngyll (), often shortened to Llanfairpwll and sometimes to Llanfair PG, is a village and community on the Isle of Anglesey, Wales. It is located on the Menai Strait, next to the Britannia Bridge. At the ...

to form two different watercourses. * Afon Braint (River Braint, Dwyran) ** Afon Rhyd y Valley (L)

Braint (ii) catchment

* Afon Braint (LlanfairPG) ** Afon Rhyd Eilian (L) ''Note "Afon Menai", known as the "

Menai Strait The Menai Strait () is a strait which separates the island of Anglesey from Gwynedd, on the mainland of Wales. It is situated between Caernarfon Bay in the south-west and Conwy Bay in the north-east, which are both inlets of the Irish Sea. The s ...

" in English, is not technically a river, despite its Welsh name.''.

Mainland rivers flowing into the
Menai Strait The Menai Strait () is a strait which separates the island of Anglesey from Gwynedd, on the mainland of Wales. It is situated between Caernarfon Bay in the south-west and Conwy Bay in the north-east, which are both inlets of the Irish Sea. The s ...
and
Caernarfon Bay Caernarfon Bay (occasionally Caernarvon Bay) is an inlet of the Irish Sea defined by the Llŷn peninsula and Anglesey. The gentle coastline surrounding it is home to villages including Nefyn, Pistyll, Trefor, Llithfaen, and Clynnog Fawr on t ...

''From Bangor Pier to the tip of the

Llŷn Peninsula The Llŷn Peninsula ( or , ) is a peninsula in Gwynedd, Wales, with an area of about , and a population of at least 20,000. It extends into the Irish Sea, and its southern coast is the northern boundary of the Tremadog Bay inlet of Cardigan Ba ...

Seiont catchment

* Afon Seiont (River Seiont) (known as Afon Rhythallt above Pont-Rhythallt) ** Afon Nant Peris (flows into Llyn Peris) *** Afon Arddu (L)

Gwyrfai catchment

* Afon Gwyrfai ** Afon Carrog (L) *** Afon Rhŷd (R)

Simple coastal catchments

* Afon Llifon * Afon Llyfni, Lleyn * Afon Desach * Afon Hen * Nant Gwrtheyrn *

Afon Geirch This is a list of rivers of Wales, organised geographically. It is taken anti-clockwise from the Dee Estuary to the M48 Bridge that separates the estuary of the River Wye from the River Severn. Tributaries are listed down the page in an upstrea ...

* Afon Amwlch * Afon Pen-y-graig

Rivers flowing into
Cardigan Bay Cardigan Bay () is a large inlet of the Irish Sea, indenting the west coast of Wales between Bardsey Island, Gwynedd in the north, and Strumble Head, Pembrokeshire at its southern end. It is the largest bay in Wales. Geography Cardigan Bay ha ...

''From the tip of the

to St. David's Head'' * Afon Saint

Daron catchment

* Afon Daron ** Afon Cyllyfelin (R)

Soch catchment

* Afon Soch ** Afon Horon (L)

Rhyd-hir catchment etc

* Afon Rhyd-hir ** Afon Penrhos (R) * Afon Erch * Afon Wen

Dwyfor catchment

Afon Dwyfor The Afon Dwyfor is a river in Gwynedd, north-west Wales, in total the river is in length. It rises in Cwm Dwyfor at the head of Cwm Pennant, gathers to itself numerous streams which drain the surrounding mountains from Mynydd Graig Goch in th ...

** Afon Dwyfach (R) ** Afon Henwy (L)

Glaslyn catchment

Afon Glaslyn is a river in Gwynedd, north-west Wales. While not of great significance in terms of its length (about ), it is one of Gwynedd's primary rivers, and has greatly influenced the landscape in which it flows. It has its source in Glaslyn, a ci ...

** Afon Dylif *** Afon Croesor (L) **

Nantmor Nantmor is a hamlet which lies about 1½ miles to the south of the village of Beddgelert in Gwynedd, Wales. The current spelling of the name Nantmor is more modernmost old documents from the 16th to the 18th century record the name as Nanmor. I ...

(L) **

(R) ** Afon Llynedno (L) * Afon Dwyryd (Headwaters are disputed to be the Afon Goedol) ** Afon y Glyn (L) ** Afon Prysor (L) ** Afon Cynfal (L) ** Afon Teigl (L) ** Afon Bowydd ** Afon Tafarn Helyg

Artro catchment

* Afon Artro ** Afon Cwmnantcol (L)

Ysgethin catchment

* Afon Ysgethin

Mawddach catchment

Afon Mawddach is a river in Gwynedd, Wales, which has its source in a wide area north of Dduallt in Snowdonia. It is 28 miles (45 km) in length, and is much branched; many of the significant tributaries are of a similar size to the main river. The c ...

** Afon Dwynant (R) ** Afon Gwynant (L) ** Afon Cwm-llechen (R) ** Afon Cwm-mynach (R) **

Afon Wnion The River Wnion is a river in the southeast of Gwynedd, Wales. It begins high on the slopes of Aran Benllyn about five miles south of Lanuwchllyn and flows south-west into the River Mawddach near Cymer Abbey. It flows past several villages, ...

(L) *** Afon Clywedog (L) *** Afon Celynog (L) ** Afon Wen (L) **

Afon Gamlan This is a list of rivers of Wales, organised geographically. It is taken anti-clockwise from the Dee Estuary to the M48 Bridge that separates the estuary of the River Wye from the River Severn. Tributaries are listed down the page in an upstre ...

(R) **

Afon Eden Afon Eden is a tributary river than runs into the Afon Mawddach in Gwynedd, Wales. It is a protected river because it is one of the few breeding grounds for freshwater pearl mussel The freshwater pearl mussel (''Margaritifera margaritifera'' ...

(R) *** Afon Crawcwellt (R) **

Afon Gain This is a list of rivers of Wales, organised geographically. It is taken anti-clockwise from the Dee Estuary to the M48 Bridge that separates the estuary of the River Wye from the River Severn. Tributaries are listed down the page in an upstrea ...

(R)

Dysynni catchment

Afon Dysynni The River Dysynni () is a river in mid Wales. Its source is the Tal-y-llyn Lake () just south of the Cadair Idris massif and its mouth is in the Cardigan Bay area of the Irish Sea to the north of Tywyn. It measures about in length. Course T ...

(R) ** Nant Cynfal (L) **

Afon Fathew The Afon Fathew () is a river in Gwynedd, north-west Wales. The river is downstream from the Dolgoch Falls which is a popular nature site, and is followed for much of its course by the Talyllyn Railway. Name The basic name of the river in W ...

(L) *** Nant Rhyd-yr-onen (L) *** Afon Cwm-Pandy (L) *** Nant Dôl-Goch (L) ** Afon Cadair (R) ** Nant Gwernol (L)

Dyffryn Gwyn catchment

* Afon Dyffryn Gwyn

Dyfi catchment

River Dyfi The River Dyfi (; ), also known as the River Dovey ( ), is an approximately long river in Wales. Its large estuary forms the boundary between the counties of Gwynedd and Ceredigion, and its lower reaches have historically been considered the b ...

(River Dovey) ** Afon Ceirig **

Afon Leri Afon Leri (; also known as the River 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. The river once f ...

(L) *** Afon Ceulan (R) ** Afon Einion (L) ** Afon Llyfnant (L) **

(R) (North Dulas) ***

Afon Deri The Afon Deri (sometimes known as the ''Afon Corris'') is a river in Mid Wales. It flows from the eastern flank of Mynydd Ty-Glas down to Corris, where it joins the Afon Dulas that flows south to the Afon Dyfi The River Dyfi (; ), also known ...

(R) ***

Nant Ceiswyn The Nant Ceiswyn (sometimes known as the ''Afon Ceiswyn'') is a small river in Mid Wales. It flows from the northern flank of Mynydd Dolgoed down to Pont Cymerau, north-east of Aberllefenni. Here it joins the Nant Llwydiarth to form the Afon Dula ...

(R) **

(L) (South Dulas) ** Afon Twymyn (L) *** Afon Rhiwsaeson (R) **** Afon Laen (L) ** Afon Angell (R) ** Afon Cleifion (L) *** Afon Dugoed (Rs) *** Afon Tafolog (Ls) ** Afon Cerist (R) ** Afon Cywarch (R)

Clarach catchment

Afon Clarach Afon Clarach (; also known as the River 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 ho ...

(formed at the confluence of Afon Stewi and Nant Silo) ** Bowstreet Brook (R) ** Afon Peithyll (Ls)

Rheidol catchment

River Rheidol Afon Rheidol (; also known as the River Rheidol) is a river in Ceredigion, Wales, in length. The source is Plynlimon. Receiving an average annual rainfall of , Plynlimon is also the source of both the Wye and the Severn. Geography and geolog ...

(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-moch (stream flowing into Nant-y-moch Reservoir)

Ystwyth catchment

River Ystwyth The River Ystwyth (; ; ) is a river in Ceredigion, Wales. The length of the main river is . Its catchment area covers . Its source is a number of streams that include the Afon Diliw, located on the west slopes of Plynlimon on the border of Cere ...

(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 The Afon Wyre ( ), (), is a small river in the county of Ceredigion, Wales; also called Afon Wyre Fawr ("Great Wyre") and formerly Gwyrai. The river runs north from its source for about 1.5 miles or 2.5 km, through Lledrod, and then t ...

** Afon Carrog (R) ** Wyre Fach (L) *** Nant Rhydrosser (L) *** Afon Tryal (L) ** Afon Beidog (L)

Cledan catchment

* Afon Cledan

Arth catchment

* River Arth

Aeron catchment

* Afon Aeron ** Afon Mydr (L) ** Gwenffrwd (R)

Coastal streams

* Afon Drywi * Afon Soden * Afon Fynnon Ddewi * Nant Hawen * Hoffnant

Teifi catchment

River Teifi The River Teifi ( ; , ), formerly anglicised as Tivy, forms the boundary for most of its length between the Welsh counties of Ceredigion and Carmarthenshire, and for the final of its total length of , the boundary between Ceredigion and Pembr ...

(Afon Teifi) ** Afon Piliau (L) ** Nant Arberth (R) **

Afon Cych Afon Cych (standard Welsh orthography: Afon Cuch) is a tributary of the River Teifi in south-west Wales. It is 13 km long, passes through a number of small settlements on the border between Pembrokeshire and Carmarthenshire, and is signific ...

(L) ***

(L) *** Afon Pedran (L) *** Afon Sylgen (R) ** Afon Hirwaun (R) ** Nant Elfed (R) ** Afon Ceri (R) *** Afon Dulas (Lampeter) (R) *** Afon Bedw (L) ** 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 Dulas (Llandyssul) (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) ** Camddwr (R) ** Afon Meurig (R) ** Nant Lluest (R) ** Glasffrwd (L) ** Nant Egnant (L) ** Nant Rhydol (R)

Nyfer catchment etc

Afon Nyfer The River Nevern () is a river in Pembrokeshire, Wales. Its source is north of the village of Crymych and its length is about to its estuary at Newport, Pembrokeshire. Course The source of the river is a spring on the southwest slope of Frenni ...

** Nant Duad (R) ** Afon Brynberian (L) ** Afon Bannon (L)

Minor coastal catchments

River Gwaun The River Gwaun ( Welsh: ''Afon Gwaun'', "''Gwaun''" meaning 'marsh, moor') is a river in Pembrokeshire, West Wales, which flows west to the sea at Fishguard (Welsh: ''Abergwaun'' - 'mouth of the Gwaun'). The Gwaun rises in the Pembrokeshire Coa ...

(Afon Gwaun) ** River Aer (L)

Rivers flowing to west Pembrokeshire coast

''From

St David's Head St David's Head () is a headland in the Pembrokeshire Coast National Park, southwest Wales, which marks the divide between the Irish Sea and the Celtic Sea. It is noted for its wildflowers and wildlife, and for the remains of ancient human set ...

to St. Govan's Head''

Minor catchments

* River Alun * River Solva (Afon Solfach) * Brandy Brook

Cleddau catchment

Daugleddau The River Cleddau () consists of the Eastern and Western Cleddau rivers in Pembrokeshire, west Wales. They unite to form the Daugleddau estuary and the harbour of Milford Haven Waterway. The name of the combined estuary – the Daugleddau – ...

(estuary is Daugleddyf or

Milford Haven Milford Haven ( ) is a town and community (Wales), community in Pembrokeshire, Wales. It is on the north side of the Milford Haven Waterway, an estuary forming a natural harbour that has been used as a port since the Middle Ages. The town was ...

downstream) **

Pembroke River Pembroke River is a short waterway near Pembroke, Pembrokeshire, West Wales. Course Rising at Hogeston Hill, near Manorbier Newton, the river meanders through Lamphey and flows past Pembroke Castle to its confluence with Milford Haven Waterwa ...

(L) ** Carew River (L) ** Cresswell River (L) **

Western Cleddau The River Cleddau () consists of the Eastern and Western Cleddau rivers in Pembrokeshire, west Wales. They unite to form the Daugleddau estuary and the harbour of Milford Haven Waterway. The name of the combined estuary – the Daugleddau – ...

(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)

Rivers flowing into the
Bristol Channel The Bristol Channel (, literal translation: "Severn Sea") is a major inlet in the island of Great Britain, separating South Wales (from Pembrokeshire to the Vale of Glamorgan) and South West England (from Devon to North Somerset). It extends ...

''From St. Govan's Head to M48 Bridge''

South Pembrokeshire rivers

* The Ritec (Afon Rhydeg}

Taf catchment

River Tâf The River Taf () is a river in West Wales. It rises in the Preseli Hills, Pembrokeshire, and continues through Carmarthenshire to Laugharne. It is one of the three rivers to enter the sea on the east side of Carmarthen Bay. The other two are ...

(Afon Taf) ** River Cywyn (Afon Cywyn) (L) ** Afon Cynin (L) *** Afon Dewi Fawr (L) *** Afon Sien (R) ** Afon Fenni (R) ** Afon Gronw (L) ** Afon Marlais (R)

Towy catchment

* Afon Tywi (River Towy) **

Afon Gwili : ''For the river which flows into the River Loughor see Afon Gwili (Loughor)'' The River Gwili () in Carmarthenshire, is a tributary of the River Towy, the longest river entirely in Wales. Its headwater is found east of Llanllawddog, in the Bre ...

(R) ** Afon Annell (R) **

River Cothi The Afon Cothi (also known as the River Cothy) in Carmarthenshire is the largest tributary of the River Tywi in south Wales. From its source at Blaen Cothi in the north of the county, north of Pumsaint, it flows south-east and then turns south ...

(R) (Afon Cothi) *** Afon Gorlech (R) ***

(R) *** Afon Marlais (R) **

(R) **

Afon Cennen The 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 Cenne ...

(L) ** Afon Sawdde (L) ** Afon Bran (L) *** Afon Ydw (R) ** Afon Dulais (R) **

Afon Brân The Afon Brân is a tributary of the River Towy (or Welsh language, Welsh Afon Tywi) 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 na ...

(L) *** Cynnant Fawr (Rs) **** Cynnant Fach (L) *** Afon Lwynor (Ls) *** Afon Crychan (L) ***

Afon Gwydderig Afon Gwydderig - geograph

The Afon Gwydder ...

(L) ** Afon Gwenlais (R) ** Gwenffrwd (R) *** Nant Melyn (R) ** Afon Doethie (R) *** Afon Pysgotwr Fawr (R) **** Afon Pysgotwr Fach (R) ** Camddwr (R)

Gwendraeth catchment

River Gwendraeth The 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. The Gwendraeth Fawr ('large Gwendraeth' in English) is surprisingly the ...

** Gwendraeth Fach (Rs) ** Gwendraeth Fawr (Ls)

Lliedi catchment

* River Lliedi (Afon Lliedi)

Loughor catchment

River Loughor The River Loughor () () is a river in Wales which marks the border between Carmarthenshire Carmarthenshire (; or informally ') is a Principal areas of Wales, county in the South West Wales, south-west of Wales. The three largest towns ar ...

(Afon Llwchwr) ** Burry Pill (L) ** Afon Lliw (L) *** Afon Llan (L) **

(R) **

River Amman The River Amman () is a river of south Wales, which joins the River Loughor at Pantyffynnon. The source of the Amman is on the Black Mountain. The river name is said to derived from the Welsh word ' "pig, piglet", reflecting the way in whic ...

(L) ** Afon Lash (R) ** Afon Morlais (R) ** Afon Dulais ** Afon Camffrwd

Clyne catchment

* Clyne River

Tawe catchment

River Tawe The River Tawe (; ) is a long river in South Wales. Its headwaters flow initially east from its source below Llyn y Fan Fawr south of Glasfynydd Forest, Moel Feity in the Black Mountain (range), Black Mountains, the westernmost range of the ...

** Nant-y-fendrod (L) ** Lower Clydach River (R) **

Upper Clydach River The Upper Clydach River runs from a poorly drained area south of Cwmgors and flows south and southeast through Cwm Gors for about 7 km to join the River Tawe at Pontardawe Pontardawe () is a town and a community (Wales), community in the ...

(R) *** River Egel (L) **

(R) *** Nant Gwys (L) **** Gwys Fawr (Ls) **** Gwys Fach (Rs) *** Nant Llynfell (R) *** Nant y Llyn (R) ** River Giedd (R) *** Nant Cyw (L) *** Nant Ceiliog (L) ** Nant Llech (L) *** Nant Llech Pellaf (L) ** River Haffes (R) ** Nant Byfre (L) ** Nant y Llyn (R)

Neath catchment

River Neath River Neath () is a river in south Wales running south west from the point at which its headwaters arising in the Brecon Beacons National Park converge to its mouth at Baglan Bay below Briton Ferry on the east side of Swansea Bay. Course U ...

** River Clydach (R) **

River Dulais River Dulais () is a river of Wales which has its source at Mynydd y Drum. It joins the River Neath after flowing over Aberdulais Falls The Aberdulais Falls are found on the River Dulais at Aberdulais, near Neath in the county borough of Neath ...

(R) ** Melin Cwrt Brook (L) ** Clydach Brook (L) **

Nedd Fechan The Nedd Fechan is a river almost wholly within the county of Powys, Wales. It rises on the eastern slopes of Fan Gyhirych in the Fforest Fawr section of the Brecon Beacons National Park and flows south for to join with the Afon Mellte at Pon ...

(Rs) ***

Afon Pyrddin The Afon Pyrddin is a river forming a short section of the boundary between Powys and Neath Port Talbot in Wales, United Kingdom. It also forms a part of the boundary of the Brecon Beacons National Park. The river and its waterfalls are one of the ...

(R) ** Afon Mellte (Ls) *** Sychryd(L) ***

Afon Hepste Afon Hepste () is a river in Powys, Wales, though partly forming the county's border with Rhondda Cynon Taf. It runs wholly within the Brecon Beacons National Park. Its headwaters, the Afon y Waun, Nant y Cwrier and Nant Hepste Fechan, rise on ...

(L) *** Afon Llia (Rs) ***

Afon Dringarth The Afon Dringarth (or simply ''Tringarth'') 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 (which is probably named after the river), the ...

(Ls)

Afan catchment

River Afan The River Afan () is a river in Wales whose valley formed the territory of the medieval Lords of Afan. The Afan Valley encompasses the upper reaches of the river. The valley is traversed by the A4107 road. Settlements in the area include Cwma ...

** Ffrwd Wyllt (L) ** Nant Cwm Wenderi ** Afon Pelenna (R) ** Nant Cregan ** Afon Corrwg (R) *** Afon Corrwg Fechan (R)

Kenfig catchment

* River Kenfig (Afon Cynffig)

Ogmore catchment

River Ogmore The River Ogmore () is a river in South Wales that is popular with Angling, anglers. It runs generally from north to south from the Ogmore Vale and Gilfach Goch, past Bridgend and Ogmore-by-Sea, Ogmore. The River Ogmore rises at Craig Ogwr (527 m ...

(Afon Ogwr) **

River Ewenny The Ewenny River () is a river in South Wales. For most of its length, it forms the border between the Vale of Glamorgan and Bridgend. It is a major tributary of the River Ogmore, which it joins near its estuary. Course The river rises to the ...

(L) ***

Afon Alun Afon Alun is a river in the Vale of Glamorgan, south Wales. It is a tributary of the Ewenny River, which it joins to the south of Bridgend. Course Two streams join near Llandow village to form the river: the Stembridge Brook and the Llandow ...

(L) *** Afon Ewenny Fach (L) *** Nant Canna (L) *** Nant Crymlyn (R) **

River Llynfi The River Llynfi (), is one of three main tributaries of the River Ogmore (). It runs for around 10 miles from its source north of Maesteg and flows generally southwards through the Llynfi Valley to the confluence with the River Ogmore and the ...

(R) *** Nant y Gadlys (R) *** Nant Cwm-du (L) **

Afon Garw The River Garw (''Afon Garw'' in Welsh language, Welsh, meaning "rugged river") runs for about 12 miles from its source in the hills north of Blaengarw to the confluence with the River Ogmore and the River Llynfi at Aberkenfig. It is one of thre ...

(R) ** Afon Ogwr Fawr (Rs) ** Afon Ogwr Fach (Ls) *** Nant Iechyd (R)

Col-huw catchment

* Afon Col-huw ** Ogney Brook (Rs) ** Hoddnant (Ls) *** Boverton Brook (Ls) *** Llanmaes Brook (Rs)

Thaw catchment

River Thaw The River Thaw () (also Ddaw) 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 ne ...

** Kenson River (L) *** River Waycock (Ls) *** Nant Llancarfan (Rs) ** Nant y Stepsau (R)

Cadoxton catchment

* Cadoxton River ** Sully Brook (L) ** Cold Brook, Cadoxton (R) *** Nant yr Argae (L) ** East Brook, Cadoxton (L) ** Bullcroft Brook (Ls) ** Wrinstone Brook (Rs)

Taff catchment

(Afon Taf) **

River Ely The River Ely () is in South Wales flowing generally southeast, from Tonyrefail to Cardiff. The river is about long. The Ely's numerous sources lie in the mountains to the south of Tonypandy, near the town of Tonyrefail, rising in the e ...

(Afon Elái) (R) ***

Afon Clun is a long tributary of the River Ely (), in the counties of Cardiff and Rhondda Cynon Taf, Wales. Its bedrock is predominantly of sandstone. Beginning on the western slope of Garth Hill, The Garth (') the river is fast-flowing, in clear shallo ...

(L) (Nant Myddlyn in upper reaches) **

River Rhondda The River Rhondda () is a river in South Wales with two major tributaries, ''Rhondda Fawr'' (meaning ''big Rhondda'') and ''Rhondda Fach'' (meaning ''little Rhondda''). Description The river has two major Tributary, tributaries, the ''Rhondd ...

(R) (Afon Rhondda) ***

Rhondda Fawr Rhondda , or the Rhondda Valley ( ), is a former coal mining, coalmining area in South Wales, historically in the county of Glamorgan. It takes its name from the River Rhondda, and embraces two valleys – the larger Rhondda Fawr valley (, 'la ...

(Ls) *** Rhondda Fach (Rs) *** River Ritec (Afon Ritec) ** Nant Clydach (R) **

River Cynon The River Cynon () in South Wales is a main tributary of the Taff. Its source is the rising of Llygad Cynon (OS grid ref SN 95240 07740) at above sea level at Penderyn, Rhondda Cynon Taf and flows roughly southeast, into the Taff at Abercynon ...

(R) (Afon Cynon) *** Aman River *** Afon Dar *** Afon Pennar ** Bargoed Taf (L) ** Nant Morlais **

Taf Fechan The River Taff () is a river in Wales. It rises in the Brecon Beacons as two rivers, the Taf Fechan ("little Taff") and the Taf Fawr ("great Taff") before becoming one just north of Merthyr Tydfil. At Cardiff, it empties into the Bristol Chan ...

(Ls) ** Nant Ffrwd (Rs)

Rhymney catchment

Rhymney River The Rhymney River () is a river in the Rhymney Valley, South Wales, flowing through Cardiff into the Severn Estuary. The river formed the boundary between the historic counties of Glamorgan and Monmouthshire until in 1887, the parishes ea ...

(Afon Rhymni) ** Nant Bargod Rhymni (R)

Usk catchment

River Usk The River Usk (; ) rises on the northern slopes of the Black Mountain (''y Mynydd Du''), Wales, in the westernmost part of the Brecon Beacons National Park. Initially forming the boundary between Carmarthenshire and Powys, it flows north int ...

(Afon Wysg) **

Ebbw River The Ebbw River (; ) is a river in South Wales which gives its name to the town of Ebbw Vale. The Ebbw River is joined by the Ebbw Fach River ( Welsh: Afon Ebwy Fach; meaning 'little Ebbw river') at Aberbeeg. The Ebbw Fach is itself fed by a left ...

(R) (Afon Ebwy) ***

Sirhowy River The Sirhowy River () is a river in Wales and a tributary of the Ebbw River. Sources The Sirhowy River has its source on the slopes of Cefn Pyllau-duon above Tredegar. After flowing through Siôn-Sieffre's Reservoir it turns south through Tred ...

(R) *** River Ebbw Fach (L) **

Afon Llwyd The Afon Lwyd or Afon Llwyd () is a long river in south-east Wales which flows from its source northwest of Blaenavon, through Abersychan, Pontnewynydd, Pontypool, Llanfrechfa and Cwmbran before flowing, at Caerleon, into the River Usk, which ...

(R) **

Sôr Brook The Sôr Brook is a right bank tributary of the River Usk running largely in Monmouthshire in south Wales, though the watercourse forms the boundary with neighbouring Torfaen in places. Its uppermost reaches were inundated by the construction o ...

(R) ** Olway Brook (L) **

Berthin Brook The Berthin Brook is a minor right bank tributary of the River Usk in Monmouthshire, in south Wales. Flowing north from New Inn New Inn () is a village and community directly south east of Pontypool, within the County Borough of Torfaen in Wales ...

(R) ** Afon Gafenni (L) (River Gavenny) *** Afon Cibi (R) ** River Clydach (R) **

Grwyne Fawr The 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 Brecknockshire, Brecon and Monmouthshire (historic) ...

(L) *** Grwyne Fechan (R) **

Rhiangoll The Rhiangoll is a river in the Brecon Beacons National Park in Powys, Wales. It rises on the western slopes of Waun Fach, highest point of the Black Mountains (Welsh: Y Mynyddoedd Duon) and drops steeply down to the west into the north–sout ...

(L) ** Nant Cleisfer (R) **

Afon Crawnon The Afon Crawnon is a river in the Brecon Beacons National Park in the county of Powys, Wales. The headwaters rise on the hills north of Trefil and flow northeast down a valley known as Dyffryn Crawnon for 7 km to a confluence with the Rive ...

(R) **

Caerfanell The 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 south-eastwards into the head of Glyn ...

(R) **

Nant Menasgin The Nant Menasgin is a short river in Powys, Wales whose headwaters rise in Cwm Oergwm, beneath Fan y Bîg, in the central Brecon Beacons, and flow northeastwards via Llanfrynach, to join the River Usk at Pencelli. The stream in Cwm Oergwm is ...

(R) **

Afon Cynrig The 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. Two rivers combine to form the Cynrig just above Cantref - these bein ...

(R) ** River Honddu (L) **

Afon Tarell The Afon Tarell is a river in Powys, Wales, which rises to the west of the Brecon Beacons in Brecon Beacons National Park and flows north, then north-east, for into the River Usk. The river is followed for its entire length through Glyn Tarell ...

(R) *** Nant Cwm Llwch **

Afon Ysgir is a 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 villa ...

(L) ** Nant Brân (L) ** Afon Cilieni (L) **

Afon Senni The 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. The river rises as Blaen Senni to the north of the ...

(R) ** Afon Crai (R) ** Afon Hydfer (R)

Wye catchment

(Afon Gwy) **

River Trothy The River Trothy () is a river which flows through north Monmouthshire, in rural south east Wales. It is a tributary of the River Wye. The river rises on Campston Hill, northeast of Abergavenny. It flows southwards until Llanvapley, where it ...

(R) **

River Monnow The River Monnow () marks the England–Wales border for much of its length. After flowing through southwest Herefordshire, England, and eastern Monmouthshire, Wales, its confluence with the River Wye is approximately south of Monmouth. The ...

(Afon Mynwy) (R) *** River Dore (L) **** Dulas Brook (R) **** Worm Brook (L) *** River Honddu (R) ***

Olchon Brook Olkhon (, also transliterated as Olchon; , ''Oikhon'') is the third-largest lake island in the world. It is by far the largest island in Lake Baikal in eastern Siberia, with an area of . Structurally, it constitutes the southwestern margin of th ...

(R) *** Escley Brook (L) **

River Lugg The River Lugg () rises near Llangynllo in Powys, Wales. From its source, it flows through the border town of Presteigne and then into Herefordshire, England. It meets its main tributary, the River Arrow, to the south of Leominster, then ...

(L) (Afon Llugwy) *** River Frome (L) ***

River Kenwater The River Kenwater or simply Kenwater is a short anabranch of the River Lugg, i.e. it splits from and later re-joins that river. It separates from it about 2 kilometres north-west of Leominster Leominster ( ) is a market town in Herefordshi ...

*** River Arrow (R) **** Cynon Brook ***** Gilwern Brook **** Gladestry Brook ** Dulas Brook (R) ** Afon Llynfi (R) *** River Ennig (R) *** Dulas (L) **** Triffrwd (L) **

Bachawy The Bachawy () (or Bach Howey on Early Ordnance Survey maps.) is a minor river in Powys, Wales. It rises in the hills north of Painscastle, flowing initially to the southeast before turning to the southwest at Rhos-goch, assuming a more westerly ...

(L) ** Afon Edw (L) ** Duhonw (R) **

Afon Irfon Afon Irfon (the River Irfon) is a river in Powys, Wales. It flows from the upper slopes of Bryn Garw in the Cambrian Mountains, through the Abergwesyn Valley, past the Nant Irfon National Nature Reserve in the hills above the village of Abergw ...

(R) *** Afon Chwerfri (L) *** Dulas (L) ***

Afon Cammarch This is a list of rivers of Wales, organised geographically. It is taken anti-clockwise from the Dee Estuary to the M48 Bridge that separates the estuary of the River Wye from the River Severn. Tributaries are listed down the page in an upstre ...

(L) ***

(R) *** Afon Gwesyn (L) ** Dulas Brook (L) **

River Ithon The River Ithon ( Welsh: Afon Ieithon) 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 L ...

(L) (Afon Ieithon) *** Dulas (R) *** Clywedog Brook (R) *** Afon Aran (L) *** Camddwr (L) **

Afon Elan is a tributary of the River Wye which runs through the wide expanse of upland moors, traditionally known as Elenydd, in central Wales. Its valley is the Elan Valley. The name probably arises from ''elain'' meaning 'hind' or 'fawn' in referenc ...

(R) *** Afon Claerwen (R) **** Rhiwnant (R) **** Afon Arban (R) **** Afon Claerddu (R) *** Afon Gwngu (R) ** Afon Marteg (L) ** Afon Bidno (L) ** Afon Tarennig (R)

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 This is a list of rivers of England, organised geographically and taken anti-clockwise around the English coast where the various rivers discharge into the surrounding seas, from the Solway Firth on the Scottish border to the Welsh Dee on the W ...

. *

(Afon Hafren),

Bristol Channel The Bristol Channel (, literal translation: "Severn Sea") is a major inlet in the island of Great Britain, separating South Wales (from Pembrokeshire to the Vale of Glamorgan) and South West England (from Devon to North Somerset). It extends ...

(Mor Hafren) ** Rea Brook (R) (small parts of upper catchment in Wales) **

River Vyrnwy The River Vyrnwy (, ) flows through northern Powys, Wales, and Shropshire, England. The name derives from Severn, the river of which it is a tributary. Course The river used to be sourced from the many rivers and streams running off the mount ...

(L) (Afon Efyrnwy) (lowermost section in England) *** Afon Tanat (L) (lowermost section in England) ****

Cynllaith Cynllaith or Cynllaeth was a commote () of north east Wales in the cantref of (later Chirkland) which was once part of the Kingdom of Powys and later part of the smaller kingdom of Powys Fadog. Cynllaith, or at least the part of it called ''C ...

(L) (part forms the border between Wales and England) ***** Afon Ogau **** Afon Iwrch (L) **** Afon Rhaeadr (L) **** Afon Eirth (L) *** Afon Cain (L) **** Nant Fyllon (Ls) **** Nant Alan (Rs) *** Afon Banwy (R) (a.k.a. Afon Einion) **** Afon Einion (R) **** Afon Gam (R) ****

(L) ** Maerdy Brook (L) ** New Cut/Guilsfield Brook (L) ** Luggy Brook (L) ** Camlad (R) (partly in England) **

River Rhiw The River Rhiw ( meaning 'slope river' or 'stream river') is a short river in the north of Powys in Wales. Two headwater tributaries both named Afon Rhiw flow east to join at Dwyrhiew and then continue in a generally easterly direction to join t ...

(Afon Rhiw) (L) *** Afon Rhiw (north fork) (Rs) *** Afon Rhiw (south fork)(Ls) ** Llifior Brook (L) ** The Mule (R) (Afon Miwl) ** Bechan Brook (L) **

Mochdre Brook Mochdre may refer to: *Mochdre, Conwy, north Wales *Mochdre, Powys Mochdre () is a small village in the community of Mochdre with Penstrowed, in Montgomeryshire, Powys, Wales. Geography About southwest of Newtown, it is near the River Sev ...

(R) ** Nant Rhyd-ros lan?? ** Afon Carno (L) *** Afon Cerniog (R) *** Afon Cledan (R) ** Afon Trannon (L) *** Afon Cerist (R) **** Colwyn Brook (L) ** Nant Feinion (R) ** Wigdwr Brook (L) ** Afon Clywedog (L) *** Afon Biga (R) (flows into Clywedog Reservoir) ***

(R) (flows into Clywedog Reservoir) **

(R) *** Afon Brochan (L) *** Nant Cydros (R) *** Rhydyclwydau Brook (R)

Longest rivers in Wales

This is a table of the longest rivers wholly or partially in Wales.Encyclopædia Britannica. 1911. "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 mathematics, a fractal is a Shape, geometric shape containing detailed structure at arbitrarily small scales, usually having a fractal dimension strictly exceeding the topological dimension. Many fractals appear similar at various scale ...

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.

References

{{Authority control

Rivers of Wales

Mainland rivers flowing into Liverpool Bay

Dee catchment

Clwyd catchment

Conwy catchment

Simple coastal catchments

Aber catchment

Ogwen catchment

Cegin catchment

Adda catchment

Isle of Anglesey Anglesey ( ; ) is an island off the north-west coast of Wales. It forms the bulk of the Principal areas of Wales, county known as the Isle of Anglesey, which also includes Holy Island, Anglesey, Holy Island () and some islets and Skerry, sker ... rivers

Minor coastal catchments

Crigyll catchment

Ffraw catchment

Cefni catchment

Braint (i) catchment

Braint (ii) catchment

Seiont catchment

Gwyrfai catchment

Simple coastal catchments

Rivers flowing into Cardigan Bay Cardigan Bay () is a large inlet of the Irish Sea, indenting the west coast of Wales between Bardsey Island, Gwynedd in the north, and Strumble Head, Pembrokeshire at its southern end. It is the largest bay in Wales. Geography Cardigan Bay ha ...

Daron catchment

Soch catchment

Rhyd-hir catchment etc

Dwyfor catchment

Glaslyn catchment

Artro catchment

Ysgethin catchment

Mawddach catchment

Dysynni catchment

Dyffryn Gwyn catchment

Dyfi catchment

Clarach catchment

Rheidol catchment

Ystwyth catchment

Wyre catchment

Cledan catchment

Arth catchment

Aeron catchment

Coastal streams

Teifi catchment

Nyfer catchment etc

Minor coastal catchments

Rivers flowing to west Pembrokeshire coast

Minor catchments

Cleddau catchment

Rivers flowing into the Bristol Channel The Bristol Channel (, literal translation: "Severn Sea") is a major inlet in the island of Great Britain, separating South Wales (from Pembrokeshire to the Vale of Glamorgan) and South West England (from Devon to North Somerset). It extends ...

South Pembrokeshire rivers

Taf catchment

Towy catchment

Gwendraeth catchment

Lliedi catchment

Loughor catchment

Clyne catchment

Tawe catchment

Neath catchment

Afan catchment

Kenfig catchment

Ogmore catchment

Col-huw catchment

Thaw catchment

Cadoxton catchment

Taff catchment

Rhymney catchment

Usk catchment

Wye catchment

Severn catchment

Longest rivers in Wales

See also

References

Isle of
Anglesey Anglesey ( ; ) is an island off the north-west coast of Wales. It forms the bulk of the Principal areas of Wales, county known as the Isle of Anglesey, which also includes Holy Island, Anglesey, Holy Island () and some islets and Skerry, sker ...
rivers

Rivers flowing into
Cardigan Bay Cardigan Bay () is a large inlet of the Irish Sea, indenting the west coast of Wales between Bardsey Island, Gwynedd in the north, and Strumble Head, Pembrokeshire at its southern end. It is the largest bay in Wales. Geography Cardigan Bay ha ...

Rivers flowing into the
Bristol Channel The Bristol Channel (, literal translation: "Severn Sea") is a major inlet in the island of Great Britain, separating South Wales (from Pembrokeshire to the Vale of Glamorgan) and South West England (from Devon to North Somerset). It extends ...