Stage 8 saw the Tour's first summit finish, atop the dormant volcano of Puy de Dôme at an elevation of , a first-category climb. Merckx initiated an early twelve-strong breakaway that included Ocaña, but it only lasted . Thereafter, Merckx and his team controlled the race until the early slopes of the cloud covered final climb. With remaining, a failed Bernard Thévenet attack was soon followed by a successful one by Ocaña, who at one point led by 40 seconds. Mountains classification leader Zoetemelk and Agostinho moved ahead of the Merckx in the final kilometre, with the two placing behind winner Ocaña. In fourth place, Merckx recovered in the final , limiting the loses to Ocaña to only fifteen seconds. Zoetemelk moved up to second overall, 36 seconds behind Merckx, with third-placed Ocaña a further second down. The next day, a group of nine riders broke away over the remainder of the Massif Central climbs and ended six minutes ahead of the peloton in Saint-Étienne. Godefroot won the sprint finish, moving him into the lead of the points classification.
