Travel Guide to Stwlan Dam in Wales

Llyn Stwlan is a mountain reservoir at an elevation of 512m (1,679ft) above the sea level, located in the county of Gwynedd, in Wales.

Llyn Stwlan

How do you get to Stwlan dam?

Tucked away in the Snowdonia National Park, on the north-west part of the country, the road to the dam (Ffestiniog Power Station) is totally paved, but narrow and curvy, with 8 hairpin turns. Starting at Tanygrisiau, the road to the dam is 2.89km (1.8 miles) long. It was built in 1957.

Is the road to Stwlan Dam open?

The road is closed to private vehicles. Chains or snow tyres can be required anytime. At the top, the views of the Moelwyn range and the Vale of Ffestiniog are outstanding. Llyn Stwlan was a small, corrie lake until the late 1950s when the dam was built as part of the Ffestiniog Hydro-Electric pumped storage scheme. Lying at 1,600 feet above sea level in the Moelwyn mountains, Stwlan is the top reservoir from which the water drops 1,000 feet to turn turbines at the Ffestiniog Power Station.

Is the road to Stwlan Dam steep?

The road to the summit is very steep, hitting a 18.4% of maximum gradient through some of the ramps. Starting at Tanygrisiau, a village within Blaenau Ffestiniog in the upper end of the Vale of Ffestiniog, the ascent is 2.89km (1.8 miles) long. Over this distance the elevation gain is 279 meters. The average gradient is 9.65%.
Pic: Gareth Jones