Tree roots in the Trois Pignons area of the Fontainebleau forest in France. Claude François Denecourt created 11 official trails during his life, with a combined length of 150 km. Later, his chosen successor, Charles Colinet continued his work and added new trails. The footpaths were abandoned and fell into disrepair during the two World Wars. After the wars, the old trails were eventually repaired and new paths added, including the "Circuit des 25 Bosses" (The 25 Bump Loop), that passes through the Trois Pignons. The latter trail was built by mountaineers in the 1970's to train for hiking in the Alps.