Due to the extreme heat and the increased risk of wildfires, a prefectural order prohibits access to the Trois Pignons national forest until July 15.
This area is very popular, especially on weekends; parking there is difficult, and you risk breaking the law.
We therefore recommend using the Rocher Cailleau parking lot instead.
You might also be interested in other, less crowded sites, such as the “Saharan dunes” accessible from the Grands Feuillards parking lot, or “Mont Blanc” in the Commanderie mountain range.
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From the entrance to Noisy-sur-Ecole, it takes about twenty minutes to reach the sand dunes via the Chemin de la Plaine de Jean des Vignes. It’s a must-see in the Fontainebleau Forest.

There you’ll find a sea of sand: the “Sables du Cul du Chien,” surrounded by trees and rocks, which are very popular with hikers, rock climbers, and horseback riders.

This geological curiosity—a vast beach without a sea—is located right in the heart of the national forest. Its origin is due to the geological evolution of the area: 30 million years ago, an ocean of warm water covered the site, depositing quartz at the bottom, which later broke down into sand.
Surrounding this vast sea of sand are sandstone boulders of all sizes. Among them is the most famous one: the “bilboquet,” standing alone in the sand.