Apparently, the EU spent a lot of money to renovate this lake and turn it into the perfect playground. The lake is about 20 min drive from Chamonix but there is so much for the kids to do there. Really a lot. Could spend 3 full days at this beach with the kids.
On the west side, there is the most fun stuff for the kids. Especially the “Passy Accro Lac”, which is a climbing track high we are something the kids love.