Mont Ventoux
Last seen: Tour de France 2009
Location: Provence, France
Height gain: 1,609m in 22km
Max gradient: 11%
Not the steepest mountain, but the climb up Ventoux is relentless, with kilometre after kilometre of 8-9% gradient which, when mixed with strength-sapping heat or storm-force winds, can break even the fittest of cyclists. Lance Armstrong called it, 'the hardest climb in the Tour, bar none.'
Monte Zoncolan
Last seen: Giro d'Italia 2010
Location: northern Italy
Height gain: 1,210m in 11km
Max gradient: 20%
The 2010 edition of the Giro was considered to be one of the best of the modern age, and it was helped by the inclusion of the Zoncolan. This brutally steep climb blew the field of riders apart and allowed Italian pro Ivan Basso to grab the lead, which he held to the finish. The hardest route up the mountain starts from the town of Ovaro and climbs gently for two kilometres before kicking up sharply to between 13% and 20% for the next 6km. Only the strongest legs can prevent an untimely dismount.
Alto El Angliru
Last seen: Vuelta a Espana 2008
Location: northern Spain
Height gain: 1,248m in 12.5km
Max gradient: 23%
Spain's answer to the Zoncolan, the Angliru is longer and steeper, and its inclusion in the Vuelta usually results in pro riders complaining about the sadistic nature of the race organisers. The climb starts gently, and gets even easier, until about six kilometres in, when it suddenly rears up to an average gradient of 13% for the next 7km, with the steepest section touching 24%. Get up this, and you can get up anything.
