Stwlan Dam

Welcome to the first of a new series celebrating Britain's best and hardest climbs. And we begin with an absolute cracker

- Words Pete Muir Photography Andrew Grant

There are many ways to assess a climb - longest, steepest, most elevation, most ascents on Strava - but how do you judge which climb is 'best'? It's a pertinent question because the Stwlan Dam climb in North Wales must be in the running for 'Best climb in Britain'.

At just under 3.5km, it's by no means the longest climb in the country, but that's still a really good length: not too short, not too long. Nor is it outlandishly steep, averaging between 9% and 10% with a peak at around 17%, but that feels like just the right steepness for a British climb: not too punishing (unlike some of the monsters to come in this series) while being enough of a challenge to give a sense of achievement.

Numbers, however, do nothing to express why Stwlan Dam deserves to be recognised as a must-visit climb for any British rider. For that we need more intangible criteria.

Firstly there's the glory of the surroundings, slap in the heart of the Snowdonia National Park with unobstructed views over a tapestry of mountains, forests and lakes. Then there's the road, which is out of bounds to motor traffic other than service vehicles for the dam, meaning the climb is car-free and the tarmac blissfully unscarred. Finally there are the sinuous switchbacks - a rarity in this country - that make it feel like a climb that has been magically transported over from the Alps, with the denouement being a finish alongside the magnificent Stwlan Dam itself.