Superb site, which really deserves its nickname "little Canada". You can do the tour in 1 hour, taking your time. The autumnal colors, with bright sunshine, are sublime. Nestled at an altitude of 900m, the water is very cool, but certainly more welcoming in summer. In winter, it is possible to skate on it when it is freezing.
A very beautiful location and perfect for overnight parking in your van (someone will come and collect the very cheap 8 euros in the morning). You can park right next to the grass by the lake for the amazing views. Swimming in the lake is great and it has its own little beach which is even supervised. There are toilets and campervan waste facilities present. We didn't visit the Auberge but it looked lovely. Thank you.