The Afon Mawddach ( en, River Mawddach, italic=yes) is a

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of wate ...

Gwynedd Gwynedd (; ) is a county and preserved county (latter with differing boundaries; includes the Isle of Anglesey) in the north-west of Wales. It shares borders with Powys, Conwy County Borough, Denbighshire, Anglesey over the Menai Strait, and C ...

, Wales, which has its source in a wide area north of Dduallt in

Snowdonia Snowdonia or Eryri (), is a mountainous region in northwestern 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 It was a commonly held belief that the nam ...

. 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 catchment area is bounded to the east by the Aran Fawddwy massif and to the west and north by the

Harlech Harlech () is a seaside resort and community in Gwynedd, north Wales and formerly in the historic county of Merionethshire. It lies on Tremadog Bay in the Snowdonia National Park. Before 1966, it belonged to the Meirionydd District of the 197 ...

dome which forms a watershed just south of

Llyn Trawsfynydd Llyn Trawsfynydd is a large man-made reservoir situated near the village of Trawsfynydd in Gwynedd, North Wales. With a total surface area of the reservoir is slightly more extensive than Wales's largest natural lake, Llyn Tegid at . History ...

. The Mawddach has been the site of significant industrialisation and land management. Gold mining and subsequently

gold panning Gold panning, or simply ''panning'', is a form of placer mining and traditional mining that extracts gold from a placer deposit using a pan. The process is one of the simplest ways to extract gold, and is popular with geology enthusiasts especi ...

have had major impacts but forestry, the preparation of animal skins, the storage of old munitions and the use of hill-sides as artillery ranges have all added to the legacy of pollution. The river is also very ''flashy'' - prone to very rapid rise and fall in level depending on rainfall. Rainfall can also be very heavy and it falls on very base-poor soils leading to episodes of strongly depressed pH. Despite this, the river sustains an important

salmon Salmon () is the common name for several list of commercially important fish species, commercially important species of euryhaline ray-finned fish from the family (biology), family Salmonidae, which are native to tributary, tributaries of the ...

and

trout Trout are species of freshwater fish belonging to the genera '' Oncorhynchus'', ''Salmo'' and ''Salvelinus'', all of the subfamily Salmoninae of the family Salmonidae. The word ''trout'' is also used as part of the name of some non-salmoni ...

fishery and the countryside through which it flows is some of the most spectacular and scenic in the UK. The main tributaries starting in the west and working clockwise are: *

Afon Cwm Mynach 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 ...

which drains Llyn Cwm Mynach on the

Rhinogydd The Rhinogydd (a Welsh plural form, often anglicised as Rhinogs and also known by the alternative Welsh plural Rhinogau) are a range of mountains located east of Harlech in North Wales. The name ''Rhinogydd'' derives from the names of two of the ...

. *

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 upstrea ...

which joins at

Ganllwyd Ganllwyd is a small village and community in southern Gwynedd, Wales. It lies in the Snowdonia National Park to the north of Dolgellau. A470 passes through it. The Community population taken at the 2011 Census was 179. Geography The villag ...

after following a tumultuous valley through ancient

oak An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably ''L ...

woods before descending towards the main river down Rhaeadr Ddu (''Black waterfalls''). This valley has one of the more important

moss Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta (''sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and hor ...

and

liverwort The Marchantiophyta () are a division of non-vascular land plants commonly referred to as hepatics or liverworts. Like mosses and hornworts, they have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of g ...

communities in the southern UK. *

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'' ...

- its headwaters known as Afon Crawcwellt - a large tributary draining from below

and closely following the

A470 The A470 (also named the Cardiff to Glan Conwy Trunk Road) is a trunk road in Wales. It is the country's longest road at and links the capital Cardiff on the south coast to Llandudno on the north coast. While previously one had to navigat ...

through the

Coed-y-Brenin Coed y Brenin (Welsh for ''King's Forest'') is a forest in the Snowdonia National Park, North Wales near Dolgellau at . It is popular for its mountain bike trails and hiking paths. It has several man-made mountain bike singletrack courses in ...

forest. This tributary has been severely affected by

industrialisation Industrialisation ( alternatively spelled industrialization) is the period of social and economic change that transforms a human group from an agrarian society into an industrial society. This involves an extensive re-organisation of an econo ...

in the past, including

gold Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile met ...

mining and its use as an

ordnance Ordnance may refer to: Military and defense *Materiel in military logistics, including weapons, ammunition, vehicles, and maintenance tools and equipment. **The military branch responsible for supplying and developing these items, e.g., the Unit ...

range. *

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 ...

, a large tributary which has also been impacted by similar problems to the Eden and is very acidic and peaty. *

Afon Wen Afon Wen is a small hamlet on the Llŷn peninsula in the Welsh principal area of Gwynedd. Location It is located at the mouth of the Afon Wen river, half a mile from the village of Chwilog and midway between Pwllheli and Cricieth. History ...

which joins south of the Gain is similar but smaller. *

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, inc ...

is a major tributary joining from the east and which drains a large area out towards Aran Fawddwy

Estuary

Below

Dolgellau Dolgellau () is a town and community in Gwynedd, north-west Wales, lying on the River Wnion, a tributary of the River Mawddach. It was the traditional county town of the historic county of Merionethshire ( cy, Meirionnydd, Sir Feirionnydd) un ...

the river enters a wide and sandy estuary of great beauty. At its mouth is the town of

Barmouth Barmouth ( cy, Abermaw (formal); ''Y Bermo'' (colloquial)) is a seaside town and community (Wales), community in the county of Gwynedd, northwestern Wales, lying on the estuary of the Afon Mawddach and Cardigan Bay. Located in the Historic coun ...

and its

railway bridge A bridge is a structure built to Span (engineering), span a physical obstacle (such as a body of water, valley, road, or rail) without blocking the way underneath. It is constructed for the purpose of providing passage over the obstacle, whic ...

The southern bank of the Mawddach estuary, along which used to run a section of the GWR branch line from

Ruabon Ruabon ( cy, Rhiwabon ) is a village and community in Wrexham County Borough, Wales. The name comes from ''Rhiw Fabon'', ''rhiw'' being the Welsh word for "slope" or "hillside" and ''Fabon'' being a mutation from St Mabon, the original church ...

, has now been designated the

Mawddach Trail The Mawddach Trail ( cy, Llwybr Mawddach) is a cycle path route, part of Lôn Las Cymru, which runs for some from Dolgellau to Morfa Mawddach railway station , by Barmouth bridge on the Cambrian coast. It is maintained by the Snowdonia Na ...

, an 8-mile cycle path running from Dolgellau to Morfa Mawddach, at the south side of the Barmouth railway bridge. It is managed by the

Snowdonia National Park Authority Snowdonia or Eryri (), is a mountainous region in northwestern 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 It was a commonly held belief that the nam ...

as a leisure route for walkers and cyclists, and is part of the

Sustrans Sustrans is a United Kingdom-based walking, wheeling and cycling charity, and the custodian of the National Cycle Network. Its flagship project is the National Cycle Network, which has created of signed cycle routes throughout the United Kin ...

Cross-Wales Cycling Route. The estuary of the Mawddach was a great centre of

ship building Shipbuilding is the construction of ships and other floating vessels. It normally takes place in a specialized facility known as a shipyard. Shipbuilders, also called shipwrights, follow a specialized occupation that traces its roots to befor ...

in the 18th century and probably for some centuries before. There is no evidence remaining of this activity in the estuary today.

External links

River Mawddach panorama

Aerial photograph of Cadair Idris and the river Mawddach

The Mawddach Trail - The 'Railway Walk' between Dolgellau and Barmouth

The Mawddach Way: A 50km Circular Walk around the Mawddach Estuary

Mawddachestuary.co.uk - Events and Activities along the Mawddach Estuary

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Mawddach The Afon Mawddach ( en, River Mawddach, italic=yes) 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 tribut ...