The River Rhythallt (
Welsh: Afon Rhythallt) 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 w ...
in
Gwynedd,
North Wales
North Wales ( cy, Gogledd Cymru) is a region of Wales, encompassing its northernmost areas. It borders Mid Wales to the south, England to the east, and the Irish Sea to the north and west. The area is highly mountainous and rural, with Snowdonia N ...
whose source is
Llyn Padarn
Llyn Padarn is a glacially formed lake in Snowdonia, Gwynedd, north Wales, and is an example of a moraine dammed lake. The lake is approximately long (about 240 acres) and at its deepest point is deep, and is one of the largest natural lakes ...
. It flows in a northwesterly direction past the village of
Brynrefail, Gwynedd and changes its name to
Afon Seiont
Afon Seiont (Welsh, meaning ''River Seiont'' in English) is a river in Gwynedd, Wales which runs into the Menai Strait.
Its source is the outflow of Llyn Padarn near Llanberis, and it flows out in a generally northwest direction. Between th ...
downstream of
Pont Rhythallt in
Llanrug
Llanrug (or Llanfihangel-yn-y-grug) is a medium-sized village and community in Gwynedd, north-west Wales. It lies about to the east of Caernarfon, south of Bangor and northwest of Llanberis. It is the largest populated village in the Arfon ...
. The Afon Seiont eventually reaches the sea at
Caernarfon
Caernarfon (; ) is a royal town, community and port in Gwynedd, Wales, with a population of 9,852 (with Caeathro). It lies along the A487 road, on the eastern shore of the Menai Strait, opposite the Isle of Anglesey. The city of Bangor is ...
. The river has a broad
flood plain which occasionally threatens homes in the village of
Cwm-y-glo
Cwm-y-glo is a small village in Wales, east of Caernarfon, between Llanberis and Llanrug. It is in the Arfon Parliamentary constituency, the community of Llanrug, and the Gwynedd Council electoral ward. Cwm-y-glo ward includes Ceunant and ...
.
Llanberis
Llanddeiniolen
Llanrug
Rivers of Gwynedd
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