CARCASSONNE, France (AP) — Vincenzo Nibali is in the yellow jersey as the Tour de France peloton set off on the longest stage, into the Pyrenees.

The Italian holds a lead of more than 4½ minutes over second-place Alejandro Valverde of Spain.

The 237.5-kilometer (147-mile) Stage 16 from Carcassonne to Bagneres-de-Luchon features an ascent up the super-tough Port de Bales.

Valverde won a stage in the 2012 Tour that had a similar climb over the Port de Bales and a finish downhill.

Before the stage, the Lampre-Merida team said world champion Rui Costa would not start due to pneumonia. The Portuguese rider had been in 13th place, about 13 minutes behind Nibali.