The reason why the Tour had never started in Italy before, is that they didn't want the Alps to come in the first week. Now they've found a creative solution by doing one Alpine stage in the first week and returning in the third week.
This stage has no less than 70 km of climbing, but mostly at a low gradient. They're not doing the Pantani/Télégraphe side of the Galibier, but the gentler Lautaret side. It's still a tough climb, because of its height and because it gets harder in the final four km. There are some steep bends shortly before the top. UAE or Visma will probably set a pace to reduce the group and prepare a possible attack in the final four km of the climb. After that comes a long, technical, dangerous descent. Hopefully there won't be any crashes.
This might go to a GC rider in a sprint with a small group or solo, but climbers who have already lost time might also have a go. Perhaps Lenny Martinez, Gaudu or Lutsenko? For Evenepoel this will be a big test. He's among the best in the low and middle mountains, but he still needs to prove that he can follow the elite climbers at high altitude. For Carapaz it won't be obvious to stay in yellow, because even if he hangs on with the best he can still lose it on bonus seconds.