Best Places to Visit in Snowdonia & Gwynedd
Written by UK Hidden Gems Editorial
Updated 5 August 2026
The best places to visit in Snowdonia & Gwynedd are Cwm Idwal National Nature Reserve, Llyn Cau, Llyn Celyn Viewpoint, Dinorwic Quarry, Borth-y-Gest, Black Rock Sands Caves, Dolwyddelan Castle and Arthog Waterfalls.
Snowdonia and Gwynedd wrap high mountains around old slate country, drowned valleys and a quiet coast. The great glacial bowls are Cwm Idwal, the first national nature reserve in Wales, ringed by cliffs below the Devil's Kitchen, and Llyn Cau in its corrie beneath Cadair Idris.
Slate has left its mark at the vast terraces of Dinorwic Quarry above Llanberis, now part of a World Heritage Site, and history clings to the ridge-top ruin of Dolwyddelan Castle and the drowned village behind the Llyn Celyn viewpoint. On the coast, the pretty village of Borth-y-Gest curves around its bay near Porthmadog, the firm sands of Black Rock hold caves at their rocky end, and the Arthog Waterfalls tumble to the Mawddach estuary opposite Barmouth.
Some are serious mountain walks, others easy coast and quarry visits. Here are eight places to visit across Snowdonia and Gwynedd.
Cwm Idwal National Nature Reserve
Photo: Ian Greig via Geograph.org.uk
Cwm Idwal is a glacial bowl in the mountains of Snowdonia, holding the dark lake of Llyn Idwal beneath a ring of cliffs. It was the first national nature reserve declared in Wales.
A path of around three miles loops the lake from the car park at Ogwen, climbing toward the cleft in the headwall known as the Devil's Kitchen. The rock walls and hanging valley draw walkers, climbers and geologists.
Llyn Cau
Photo: Andrew Wood via Geograph.org.uk
Llyn Cau Locked into a deep rock hollow under the summit of Cadair Idris, this dark, glass-clear corrie lake is walled on three sides by the sheer face of Craig Cau. The Minffordd Path grinds up from the car park on the south side, a proper haul past falls and pools before it swings round the rim of the crag toward the mountain top.
A small stony beach on one shore tempts walkers to rest and swimmers to take the plunge into cold water. Local tales have long insisted the lake has no bottom at all, a story the brooding setting does nothing to dispel.
Llyn Celyn Viewpoint
Photo: Jeff Buck via Geograph.org.uk
Llyn Celyn is a large reservoir in the Tryweryn valley west of Bala, in Snowdonia, with a viewpoint and parking along the A4212. The lake was made in the mid-1960s by damming the valley, and in doing so it drowned Capel Celyn, a Welsh-speaking village with its chapel, school and post office.
The flooding, to supply water to Liverpool, became a rallying point for Welsh national feeling, remembered in the slogan Cofiwch Dryweryn. A memorial chapel and garden built in 1971 near the water hold gravestones moved from the old village cemetery.
Below the dam, the River Tryweryn feeds a white-water centre.
Dinorwic Quarry
Photo: Brian Deegan via Geograph.org.uk
Dinorwic Quarry is a vast disused slate quarry cut into the side of Elidir Fawr above Llanberis in Snowdonia. Great stepped terraces and galleries climb the mountainside, scattered with ruined sheds and heaps of broken slate, left as they were when the quarry closed in 1969.
The National Slate Museum stands at its foot in the old workshops, and a pumped-storage power station is buried deep inside the mountain. The quarry is now part of a World Heritage Site covering the slate landscape of north-west Wales.
Borth-y-Gest
Photo: David Medcalf via Geograph.org.uk
Borth-y-Gest is a small, pretty village curved around a sheltered bay just south of Porthmadog, on the edge of the Glaslyn estuary. Rows of neat Victorian houses in soft colours run down the hillside to the waterfront, where small boats sit on the sand at low tide and the wide estuary opens out toward the sea.
It was once a shipbuilding place, and schooners were once built here on the shore for carrying slate. Around the headland to the west lie a string of little sandy and pebbly coves, reached on foot, quieter than the main bay.
It is a calm, old-fashioned spot, good for a stroll along the front and out to the coves.
Black Rock Sands Caves
Photo: STEVE POVEY via Geograph.org.uk
Black Rock Sands is a broad, flat beach of firm sand near Porthmadog, one of the few beaches in the country where you can drive a car straight onto the sand. It stretches wide and open at low tide, backed by dunes, with a dark rocky headland at its western end that gives the beach its name.
Among those rocks, uncovered when the tide is out, are caves and pools worth exploring, cut into the headland and full of seaweed and small sea creatures. The main draw is the size and openness of the place, with views across Tremadog Bay to the mountains of the Llyn and Snowdonia, and the rocky end its quieter, more interesting corner.
Dolwyddelan Castle
Photo: Eric Jones via Geograph.org.uk
Dolwyddelan Castle is a ruined native Welsh castle on a rocky ridge just west of Dolwyddelan village in Snowdonia, built by Llywelyn the Great, prince of Gwynedd, in the early thirteenth century to guard a mountain route. Edward I took it in 1283.
The surviving rectangular keep was heightened and largely rebuilt in a Victorian restoration in the 1840s, and it stands with the ruins of a second tower and enclosure walls, looking out over the hills. Cadw looks after it.
Tradition links Llywelyn's birth to the site, though he was more likely born at the earlier Tomen Castell nearby.
Arthog Waterfalls
Photo: Peter S via Geograph.org.uk
Arthog Waterfalls The Afon Arthog throws itself off the high ground near the Cregennan Lakes and tumbles almost to sea level in a hurry, a long chain of cascades and pools crashing down a steep wooded slope above the Mawddach estuary, across the water from Barmouth. The path alongside climbs hard through oak woodland strewn with moss and boulders, footbridges hopping back and forth over the noisy stream.
Near the bottom it meets the old railway line, now a flat walking and cycling route with sweeping views over the estuary to Barmouth and the sea. Many climb one way and loop back along the water, or press on to the lakes above.
FAQs
Which places in Snowdonia are serious mountain walks?
Cwm Idwal loops its dark lake beneath the cliffs and the Devil's Kitchen on a path of around three miles from Ogwen, and Llyn Cau is reached on the Minffordd Path up Cadair Idris, a good uphill pull past falls and pools. Both sit in dramatic glacial bowls and draw walkers, climbers and geologists.
What can you see at Dinorwic Quarry?
Dinorwic Quarry above Llanberis is a vast disused slate quarry, its stepped terraces and ruined sheds left as they were when it closed in 1969, with the National Slate Museum at its foot and a pumped-storage power station inside the mountain. It is part of a World Heritage Site covering the slate landscape of north-west Wales.
What is the story behind Llyn Celyn near Bala?
Llyn Celyn was made in the mid-1960s by damming the Tryweryn valley, drowning the Welsh-speaking village of Capel Celyn to supply water to Liverpool. It became a rallying point for Welsh national feeling, remembered in the slogan Cofiwch Dryweryn, and a memorial chapel near the water holds gravestones moved from the old village.
Conclusion
Snowdonia and Gwynedd wrap high mountains around slate country, drowned valleys and a quiet coast. The glacial bowls of Cwm Idwal and Llyn Cau sit beneath their cliffs, and slate has left its terraces at Dinorwic above Llanberis, now a World Heritage Site.
History clings to the ridge-top ruin of Dolwyddelan Castle and the drowned village behind the Llyn Celyn viewpoint. On the coast, Borth-y-Gest curves around its bay near Porthmadog, the firm sands of Black Rock hold caves at their rocky end, and the Arthog Waterfalls tumble to the Mawddach estuary opposite Barmouth.
From glacial corrie to estuary sands, these are the places to seek out across Snowdonia and Gwynedd.
