Briton Chris Froome's bid for a fifth Tour de France title will come on the shortest route of the 21st century and see a return to Alpe-d'Huez.
A hilly time-trial in the Basque Country could be decisive on the penultimate day of the race, which begins on July 7 and concludes in Paris on July 29.
Organisers unveiled the route in Paris on Tuesday. Alpe-d'Huez is not likely to be as decisive as it was in 2015 when Froome won overall by one minute 21 seconds.
Froome (Team Sky) clung on to claim a second Tour victory, after his 2013 triumph and crashing out of the 2014 edition, when struggling with a chest infection on Alpe-d'Huez, where Colombia's Nairo Quintana's (Movistar) attack up the 21-hairpins almost brought him victory.
The 105th edition of the Tour will see a reduced peloton, with each team reduced by one rider from nine to eight in Grand Tours in a bid to make the racing less controllable. Some suggested it was specifically targeted at Froome's dominant Team Sky squad.
Froome has won four of the last five editions of the Tour, while Sir Bradley Wiggins won the yellow jersey in the 99th edition of the race in 2012 to give Team Sky five victories in six years.
It was already known the race will begin on Noirmoutier-en-l'Ile and the peloton will cross the Passage du Gois causeway. The 2011 race had the same start in the Vendee region of western France.