From Pen-y-Pass to Glaslyn




5 miles (8kms)

1509ft (460m)

About the walk

Tucked beneath the cold, hard rocks of Glyder Fawr and Crib Goch, the high Pass of Llanberis would have been an awesome sight for early travellers. There wasn’t a road until 1830, so traders and farmers would have had to take their horse-drawn sledges over the boulder-strewn and boggy ground you still see away from the path. With the building of the road came an inn, where weary travellers could rest. Initially it came a poor second in popularity to the Pen-y-Gwryd Inn, a mile (1.6km) back along the road to Capel Curig, until the enterprising Owen Rawson Owen took over in 1900.

Today, you start your walk on the slabbed rocks of the Pyg Track. Or should that be the Pig Track? Opinion is divided. If it’s the Pig Track, then the name derives from Bwlch y Moch, which means pass of the pig. Pyg would come from the initials of Pen-y-Gwryd. Reaching Bwlch y Moch after the initial climb, you gaze down on Cwm Dyli and its lake, Llyn Llydaw. Snowdon’s highest peak, Yr Wyddfa, peeps over the shoulder of Crib Goch, but centre stage belongs to the immense cliffs rising from Llyn Llydaw’s shores to the twin summits of Y Lliwedd.

According to legend, King Arthur was slain at the nearby Bwlch y Saethau (‘pass of the arrows’) after a battle with his mortal enemy, Mordred. While Arthur’s body was taken down the mountainside, many of his Knights of the Round Table, feeling that their king would return, retreated to a cave where they still wait. The path climbs to overlook Glaslyn, whose waters are cradled beneath Yr Wyddfa’s dark cliffs. Legend has Glaslyn as bottomless, and home to Afanc, a fearsome monster who was thrown into its depths after gorging on too many damsels in distress – it’s a good story, but nobody’s seen him since.

After descending to Glaslyn, you follow the Miners’ Track past the stark remains of the Britannia Mine, founded in the 18th century. Originally the ore had to be hauled up the mountainside to Bwlch Glas, then down on horse-drawn sledges to Rhyd Ddu where it continued by horse and cart to Caernarfon. However, the building of the Miners’ Track and the causeway across Llyn Llydaw in 1853 made it possible for the ore carts to be taken to Pen-y-pass. The mine closed in 1926.

Walk directions

From the far right of the car park go through a gap in the wall and follow the popular path up rough slopes high above the Pass of Llanberis. It’s steep and rocky in places but well-engineered and so never really difficult. After a particularly steep climb, the gradient eases and the path reaches Bwlch y Moch, a wild pass on the northern ridge of Snowdon’s horseshoe.

Ignoring the smaller path to the summit of Crib Goch, cross a stile and follow the wide path that rounds the corner to traverse Crib Goch’s lower slopes. It’s level at first, but then climbs again, picking its way across the slopes high above Llyn Llydaw. On the skyline above look out for walkers crossing the knife-edged ridges of Crib Goch and Crib-y-Ddysgl.

The path swings round a shoulder overlooking Glaslyn’s outflow, opening up a full view of the lake, cupped between the rocky ridges of Yr Wyddfa and Garnedd Ugain. Continue along the path, still climbing slightly, across the slope high above the lake. Ahead you can see that the path steepens again to climb the infamous Zig-Zags to Bwlch Glas on the skyline, but you’re leaving before that.

When you’re above the western shores of Glaslyn, look for an engineered path climbing from the left. The junction is clearly marked by a standing stone. You may see a few people descending before this point, but don’t be tempted to follow their example. Such shortcuts are unpleasant, spread erosion, and could be dangerous. Follow the main path down scree slopes to the lake shore.

Here you pick up the Miners’ Track, a wide, flinted road that traces Glaslyn’s shoreline. It’s basically all downhill, and much easier underfoot, from here on. The track descends past the waterfalls of Glaslyn’s outflow and down to the shores of Llyn Llydaw, where it passes the ruins of the ore-crushing mill belonging to the Britannia Mine.

After the ruins the track swings right to cross the lake, using the causeway. Descending once more, the track soon rounds a rocky knoll to traverse the hillside above Llyn Teyrn, smallest of the three tarns on this walk. Looking over Llyn Teyrn, you get a fine view of the valley of Nantgwynant, with Moel Siabod rising behind it.

Beyond Llyn Teyrn the track swings left around less steep, but still rugged, slopes to make the final descent to the car park.

Additional information

Engineered paths

High mountain corries and tarns

Sheep around in summer – keep dogs on a lead

OS Explorer OL17 Snowdon / Yr Wyddfa

Pen-y-pass car park (get there early or use Nant Peris Park-and-Ride)

At car park

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About the area

Discover Gwynedd

The county of Gwynedd is home to most of the Snowdonia National Park – including the wettest spot in Britain, an arête running up to Snowdon’s summit that receives an average annual rainfall of 4,473mm. With its mighty peaks, rivers and strong Welsh heritage (it has the highest proportion of Welsh-speakers in all of Wales), it’s always been an extremely popular place to visit and live. The busiest part is around Snowdon; around 750,000 people climb, walk or ride the train to the summit each year.

Also in Gwynedd is the Llyn Peninsula, a remote part of Wales sticking 30 miles out into the Irish Sea. At the base of the peninsula is Porthmadog, a small town linked to Snowdonia by two steam railways – the Welsh Highland Railway and the Ffestiniog Railway. Other popular places are Criccieth, with a castle on its headland overlooking the beach, Pwllheli, and Abersoch and the St Tudwal Islands. Elsewhere, the peninsula is all about wildlife, tranquillity, and ancient sacred sites. Tre’r Ceiri hill fort is an Iron Age settlement set beside the coastal mountain of Yr Eifl, while Bardsey Island, at the tip of the peninsula, was the site of a fifth-century Celtic monastery.