Llyn Gwynant: Nantgwynant Lake Guide

Llyn Gwynant lies in the heart of Nantgwynant, a valley that many consider the most beautiful in Wales. The A498 runs along the shore between the lake and the woods above it, providing a drive of extraordinary quality at any time of year. The lake itself is a popular destination for wild swimming, camping and photography, with views up to Yr Wyddfa (Snowdon) that rival even Llynnau Mymbyr on a still morning.

Quick Facts

Altitude: 100m
Access: A498 along the shore; lakeside campsite at the head of the lake
Best for: Wild swimming, photography, camping, valley walking
Nearest village: Beddgelert

The Lake

Llyn Gwynant is roughly one kilometre long and 200 metres wide, sitting on the floor of a wide glacial valley flanked by steep, heavily wooded hillsides. The Afon Glaslyn flows through the lake and on through Llyn Dinas and the dramatic Aberglaslyn gorge below Beddgelert, eventually reaching the sea at Porthmadog. The valley floor is flat and fertile, with old oak and ash woodland clinging to the slopes above the lake and several small farms surviving in the traditional pattern of upland Welsh agriculture.

The views across the lake take in the slopes of Yr Wyddfa above the treeline, and on calm mornings the hills are clearly reflected in the lake surface. The lakeside campsite at the head of the lake occupies a beautiful setting and is one of the best-loved campsites in Eryri.

Getting There

The A498 between Beddgelert and Capel Curig runs directly alongside the lake. There are several small lay-bys for photography and lake access. The Watkin Path, the longest and one of the most dramatic routes to the summit of Yr Wyddfa, starts from Pont Bethania, between Llyn Gwynant and Llyn Dinas on the A498.

What You Will See

Wild swimming in Llyn Gwynant is popular throughout the summer; the shallow entry points near the lay-bys are the most used, and the usual cold-water precautions apply (see our guide to wild swimming in Eryri). Goosanders and grey wagtails are regular on the river where it enters the lake. The woodland above the lake holds pied flycatcher, wood warbler and redstart in summer, species that depend on the ancient sessile oak woodland of the Welsh valleys. In autumn the combination of turning oak leaves, calm lake water and the first snow on the summit of Yr Wyddfa produces landscape photography conditions that attract visitors from across Britain.

Swimming and Paddling

Eryri National Park lists Llyn Gwynant among the popular spots for swimming and water sports, and outdoor centres and school groups use the lake for paddling. Access is from the roadside lay-bys along the A498. The water is cold even in high summer, and clear water can look shallower than it is, so walk in slowly rather than jumping, never swim alone, and wear a bright cap and tow float so boats and paddlers can see you. On hot, still days check the edges for any discoloured or scummy water and stay out if you are in doubt, especially with dogs.

If you bring a paddleboard, kayak or wetsuit from another lake, follow Check, Clean, Dry: check for mud and plant fragments, clean your kit, and let it dry fully before using it here. This helps stop invasive species spreading between Eryri’s lakes. Please take all litter home and avoid parking on verges, which damages the lakeside and blocks a narrow road.

Walks Around the Lake

The A498 hugs one shore, but several good walks start close to the lake. From Pont Bethania, between Llyn Gwynant and Llyn Dinas, the Watkin Path climbs through woodland past the waterfalls and pools of Cwm Llan, and you can go as far as you like before turning back; the lower section makes a fine half day even if you have no plans to reach the summit. Much of the land between the two lakes, including Hafod y Llan, is looked after by the National Trust. Down the valley, the path along Llyn Dinas leads towards Dinas Emrys, the wooded hill linked with the legend of the red and white dragons, and on to Beddgelert. The valley’s scenery has also drawn film crews; see Eryri on screen: film and TV locations.

Camping and Staying

There is a campsite at the head of the lake and another on the lakeside, plus a National Trust campsite at Hafod y Llan near the start of the Watkin Path. Bryn Gwynant, a Victorian house in the valley, operates as a youth hostel. All are popular in summer, so book well ahead. Wild camping is not generally permitted in Eryri without the landowner’s permission.

Getting There by Bus

The Sherpa’r Wyddfa S4 runs through Nant Gwynant between Beddgelert, Pont Bethania and Pen-y-Pass, with connections from Porthmadog. It is a useful way to avoid the lay-by scramble on busy days and to walk one way along the valley. Check Traveline Cymru or the Sherpa’r Wyddfa timetable for current times.

Frequently Asked Questions

Can you swim in Llyn Gwynant?

Yes, and it is a popular spot for lake swimming. There are no lifeguards, so take full cold-water precautions and swim with someone else.

Where do you park for Llyn Gwynant?

Small lay-bys line the A498 beside the lake. They fill quickly in summer, so arrive early or use the S4 bus, and never block gateways or passing places.

Is Llyn Gwynant good for families?

Yes, for a picnic, a paddle at the edge or a short stroll, with campsites close by. Keep children closely supervised near the water, as clear lake water is often deeper than it looks.