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 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), 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 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 mapping and thus many of the main rivers of Wales (as defined by Natural Resources Wales ). Difficulties arise otherwise in determining what should and what should not be included. [1]
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).
From Dee Estuary to Garth Pier, Bangor, Gwynedd
Anticlockwise from Menai Bridge / Porthaethwy
The Afon Braint bifurcates near Llanfairpwllgwyngyll to form two different watercourses.
Note "Afon Menai", known as the "Menai Strait" in English, is not technically a river, despite its Welsh name..
From Bangor Pier to the tip of the Llŷn Peninsula
From the tip of the Llŷn Peninsula to St. David's Head
From St David's Head to St. Govan's Head
From St. Govan's Head to M48 Bridge
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 table of the longest rivers wholly or partially in Wales. [2] 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 | Notes | ||
---|---|---|---|---|
(miles) | (km) | |||
1 | River Severn | 220 | 354 | Longest river in the United Kingdom; leaves Wales after 48 miles (77 km). |
2 | River Wye | 135 | 217 | Forms the Wales-England border for much of its length. |
3 | River Teme | 81 | 130 | Entirely in England after 12 miles (19 km). |
4 | River Usk | 78 | 126 [3] | Longest river entirely in Wales according to some sources. [4] |
5 | River Tywi | 75 | 121 | |
6 | River Teifi | 73 | 117 | [5] |
7 | River Dee | 70 | 113 | |
8 | River Taff | 40 | 64 |
The River Taff is a river in Wales. It rises as two rivers in the Brecon Beacons; the Taf Fechan and the Taf Fawr before becoming one just north of Merthyr Tydfil. Its confluence with the River Severn estuary is in Cardiff.
The River Teifi in Wales forms the boundary for most of its length between the counties of Ceredigion and Carmarthenshire, and for the final 3 miles (4.8 km) of its total length of 76 miles (122 km), the boundary between Ceredigion and Pembrokeshire. Its estuary is northwest of Cardigan, known in Welsh as Aberteifi, meaning 'mouth of the Teifi'. Teifi has formerly been anglicised as "Tivy".
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. According to Sir Ifor Williams, the word "Glyder" derives from the Welsh word "Cludair", meaning a heap of stones.
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.
The River Rhondda is a river in South Wales with two major tributaries, Rhondda Fawr and Rhondda Fach.
The River Cynon in South Wales is a main tributary of the Taff. Its source is the rising of Llygad Cynon at 219 m (719 ft) above sea level at Penderyn, Rhondda Cynon Taf and flows roughly southeast, into the Taff at Abercynon in the same district. The water emerging at Llygad Cynon has been traced back to the sink of the Nant Cadlan at Ogof Fawr.
Llyn y Fan Fach is a lake of approximately 10 hectares on the northern margin of the Black Mountain in Carmarthenshire, South Wales and lying within the Brecon Beacons National Park. The lake lies at an altitude of approximately 1,660 feet (510 m), immediately to the north of the ridge of the Carmarthen Fans. It is the smaller of two lakes within this mountain massif: the slightly larger Llyn y Fan Fawr is about 2 miles (3.2 km) to the east.
The Nedd Fechan is a river almost wholly within the county of Powys, Wales, currently administered as part of the unitary authority of Powys. It rises on the eastern slopes of Fan Gyhirych in the Fforest Fawr section of the Brecon Beacons National Park and flows south for 7 miles (12 km) to join with the Afon Mellte at Pontneddfechan, their combined waters continuing as the River Neath to the sea near Swansea. The only significant tributary of the Nedd Fechan is the Afon Pyrddin which joins it at Pwll Du ar Byrddin. Downstream of this confluence it forms the boundary between Powys to its east and Neath Port Talbot to its west.
The 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 5 km / 3 mi to its confluence with the Afon Twrch at Cwm-twrch-Uchaf.
Llyn Cwm Llwch is a small lake or pool in the Brecon Beacons National Park in Powys, Wales. It is between 1 and 2 acres: much smaller than the two glacial lakes in the west of the Black Mountain (range): Llyn y Fan Fawr and Llyn y Fan Fach, and one of the few natural bodies of water in the park. It is of glacial origin, occupying a rock hollow beneath the peaks of Pen y Fan and Corn Du in the central Brecon Beacons. It is drained by the Nant Cwm Llwch which empties into the Afon Tarell, which itself enters the River Usk at Brecon. Tommy Jones' obelisk, a memorial in granite to a young boy who died near this spot in 1900, overlooks the lake.
The Afon Sawdde is a river in the county of Carmarthenshire, Wales. For most of its course it flows through the Brecon Beacons National Park and Fforest Fawr Geopark.
Penmoelallt or Onllwyn is a hill in the northern part of the county borough of Rhondda Cynon Taff in south Wales. It lies within the Brecon Beacons National Park and Fforest Fawr Geopark. To its east lies the deep valley of Cwm Taf and to its north a rather shallower valley in which the Nant Cadlan originates. To the west is the hill known as Mynydd-y-glog and to the south are slopes draining into the River Taff and the Afon Cynon. The hill culminates in a broken plateau with several knolls rising above the 420m contour. Its afforested nature makes it difficult to determine the precise location of its highest point but this probably lies somewhere around OS grid ref SO 003096. Older maps indicate a spot height of 1376 ft above sea level at SO 000090.
The Afon Sychryd is a river in Rhondda Cynon Taf, Wales. Although it is a relatively short river, with a total length of 3 miles (5 km), it is notable for the gorge and two waterfalls through which it flows.
The Afon Dulas is a river in Powys, Wales. It is a headwater tributary of the River Severn, which it joins at Llanidloes opposite the confluence with the Afon Clywedog. Its principal tributary is the Afon Brochan. The total length of the Dulas and Brochan is 19.6 km. Other tributaries include Nant Cydros, the Rhydyclwydau Brook and Nant Gynwydd.
The Afon Gwyrfai is a short river in Gwynedd, Wales. For half of its length it flows through Snowdonia National Park. Exiting Llyn y Gader it flows north through the small village of Rhyd-ddu to enter the southeastern end of Llyn Cwellyn. Downstream of the lake it flows northwest past Betws Garmon, leaving the national park and continues to the southern edge of Waunfawr. It then turns slightly west to flow on to Bontnewydd beyond which it turns slightly south to enter Foryd Bay. The tidal channel within the bay flows north into the western end of the Menai Strait. Principal tributary streams include the Afon Treweunydd which contributes water from the reservoir of Llyn Ffynnon-y-gwas and from the lakes of Llyn Glas, Llyn Coch and Llyn Nadroedd in Cwm Clogwyn immediately west of the summit of Snowdon. The tidal channel of the Gwyrfai within Foryd Bay also accepts the flow of the left bank tributaries, the Afon Foryd, Afon Rhyd and Afon Carrog. The river is shadowed by the line of the Welsh Highland Railway for much of its length, and by which it is crossed four times.