Swimming in Llyn Gwynant

Campers at Llyn Gwynant are welcome to swim in the lake and river, and many people do.

The water quality is good (we have it regularly tested), though a sandy bottom means that the water is not always completely clear. The local underwater diving club has visited and taken images of flora and fauna in the lake, and have documented a healthy ecosystem, view images on our underwater wildlife page.

Swimming of course depends on the weather, but be aware that the water can be cold: the lake is fed by mountain streams flowing into the Afon Glaslyn river from the summit of Snowdon itself, bringing very cold currents.

Children should be supervised at all times and be aware that the river can be suddenly turbulent: there is a hydro power plant just upstream of the river which suddenly empties into the river at unpredictable times, bringing turbulence to the little stream and pools near the stone bridge.