From the short, steep Ardennes hills to energy-sapping slogs up the toughest climbs in the Alps, Pyrenees and Dolomites, there’s no shortage of leg-numbing climbs for professional cyclists to conquer as they fight for glory in the sport’s greatest races.
But which climbs cause even the world’s best riders to come in cold sweats whenever a route is announced and race approaches? Which ascents stand above all the others – literally in some cases – when it comes to eye-watering gradients, brutal slopes and gruelling pitches?
We’ve rounded up 16 of the WorldTour’s toughest climbs over the following pages – how many have you tackled? And are there any ascents from your bucket list that you’d have included? Let us know in the comments below.