Page Contributor(s): Nathan Allen, Wales
Cycling the incomparable Stwlan Dam, Wales
Ride 1.8 miles gaining 916’ at 10% average grade.
We asked Simon Warren to provide us with lists of the Top 10 Hardest and Top 10 Most Epic bike climbs in England, Wales, Scotland, and the UK. Simon ranked Stwlan Dam as the most epic bike climb in Wales and #2 in the UK, just behind Scotland’s epic climb, Bealach-Na-Ba. We relied heavily on Simon Warren’s Top UK Climbs Series in ranking and documenting UK bike climbs (https://www.100climbs.co.uk/books) - they are the Gold Standard for cycling climbing in the UK.
Start the climb at the eastern edge of Tanygrisiau by riding up a roadway free of motor vehicles.
Climb summary by PJAMM’s Brad Butterfield:
If Bwlch y Groes is the Crown Jewel of Wales, then Stwlan Dam is Crown Pearl…hm I’m not sure that analogy makes much sense - but you get the point. There is a gate at the bottom of the climb with a gate for hikers to walk through. Unless you’re really good at Tetris, you’ll need to lift your bike over the fence; the gate is a bit tight to fit a bike through.
Giant skree pile to our right just after beginning the climb.
Tanygrisiau Reservoir at our backs as we climb.
Of course, your sheep friends will keep you company throughout the winding climb, but you most likely won’t see anybody else. Massive, imposing boulders line the roadway and the impressive dam is in sight for the last third of the climb. Switchbacks take you up the the dam, and if you're so inclined, hop the gate and ride across the actual dam for some unforgettable views of the road below and the lake held hostage by this remarkable cement engineering project.
What’s a climb in Wales without sharing it with free range sheep?
Photos nearing the top of the climb.
Epic set of seven hairpins leading to the dam: 2/10ths of a mile at 11.5%.
The imposing Stwlan Dam is the cherry on top of this epic bike climb.
Lyn Stwlan Reservoir was created by the Stwlan Dam. The first dam on this site was constructed in 1898 as part of a hydroelectric project in the area. The reservoir fills and enlarges a glacially formed lake that obviously preexisted the dam. The current dam is 800’ across and 110’ high. Construction began on the current dam in 1957.
Below climb summary by PJAMM Cyclist’s Tayler Hockett:
I’d make a day of this! A truly amazing climb that twists up through ferns and roaming/grazing sheep to reach the dam. The view, smooth pavement, lush green ferns, and wandering sheep make this a must-do ride. Sitting at the top you hear the stillness and water, your friends can cheer you on as you watch them ride from the top. Bikes are not allowed on the dam but standing at the lookout point you can see the size and power of the hydroelectric bound surging water that you’d never know was there but for the physical struggle to the top. Bring food and water as there is not a lot going in the small, quiet town where the climb begins.
That’s a wrap!
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