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 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 19 ...

dome which forms a watershed just south of Llyn Trawsfynydd. The Mawddach has been the site of significant industrialisation and land management. Gold mining and subsequently gold panning 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 and trout 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 which drains Llyn Cwm Mynach on the Rhinogydd. *

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 after following a tumultuous valley through ancient oak woods before descending towards the main river down Rhaeadr Ddu (''Black waterfalls''). This valley has one of the more important moss 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 ...

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 Llyn Trawsfynydd 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 in the past, including gold mining and its use as an ordnance 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 the river enters a wide and sandy estuary of great beauty. At its mouth is the town of Barmouth and its

railway bridge A bridge is a structure built to 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, which is usually someth ...

The southern bank of the Mawddach estuary, along which used to run a section of the GWR branch line from Ruabon to Barmouth, has now been designated the Mawddach Trail, 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 K ...

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 ...