Almost forty riders - around a quarter of the race's peloton at the start of the stage - made it into the early breakaway after around , including three riders in the lower reaches of the top twenty placings overall, mountains classification leader Fredrik Kessiakoff (Astana) and stage-winners Thomas Voeckler of Team Europcar and FDJ-BigMat rider Pierrick Fédrigo. Voeckler and Kessiakoff led the group over the top of the Col d'Aubisque, with the group remaining together until the foot of the Col du Tourmalet. Here, the group started to fragment after Garmin-Sharp's Dan Martin accelerated with Kessiakoff and Rabobank's Laurens ten Dam in tow. BMC Racing Team rider George Hincapie, Chris Anker Sørensen of Saxo Bank-Tinkoff Bank and Saur-Sojasun's Brice Feillu later joined the group up front, but only Voeckler and Feillu remained together at the top of the climb, where Voeckler further cut into Kessiakoff's polka-dot jersey lead. The peloton crossed the summit around ten minutes later.