Col du Tourmalet (west from Luz-Saint-Sauveur)

The longer, harder, and arguably more beautiful western approach climbs from the thermal town of Luz-Saint-Sauveur through Barèges, gaining 1,404m over 18.5km at 7.6% average. The first 8km through the Vallée de Bastan are deceptively gradual, but from Barèges the road pitches up and the gradient averages over 9% to the summit. This is the side that broke riders in the 2010 Tour when Andy Schleck attacked and Alberto Contador followed — the Tour passes this way more often than the eastern side. The upper slopes above Barèges are bleak, exposed moorland with no shelter from wind or rain.