The sandstone boulders scattered through the Forest of Fontainebleau are one of the world's great climbing destinations, and the oldest organised bouldering area on earth. Colour-coded circuits wind through the forest, graded from easy yellow and orange problems to the fearsome black and élite white circuits. The rock demands precise footwork and strong fingers — the rounded sandstone edges and slopers are unlike anything else in Europe.
The most popular areas for beginners are the Bas Cuvier and Rocher Canon circuits near the road, where easy access and well-travelled problems make it straightforward to start. More experienced climbers head deeper into the forest to areas like Cuvier-Rempart, Isatis, and Franchard Isatis. Shoes can be rented and lessons taken in town; the tourist office stocks circuit maps.