The 'queen' stage of the race comes with three climbs, each getting notably tougher. The Marie- Blanque isn't high but its last 4km average 10 per cent.
The Soulor is longer, higher and tackled from its toughest side. Then to the Tourmalet, the highest climb of this year's race. It's debatable whether this side is the tougher of the two ascents, but there's no doubt it's tough enough to make a real difference.
Steepest in the town of Barèges and then towards the summit, the Tourmalet offers little respite to what will be very Tour-weary legs.