Circuit des 25 Bosses

The 'Circuit des 25 Bosses' (The 25 Bumps) is located in the Massif des Trois Pignons, on the western edge of the Forêt de Fontainebleau. Originally established in the 1970s as a training ground for alpinists, this technical 16km loop remains one of the most demanding day hikes in the Île-de-France region. The trail requires hikers to cross 25 distinct sandstone ridges, involving frequent scrambling over boulders and navigating deep sandy paths. It is an intense physical challenge characterized by constant elevation changes and a unique ecosystem of maritime pines and white sand dunes. Note: Compiled from public sources — not a field report.

The Nahuel Huapi Traverse is a multi-day hut-to-hut route that circumnavigates the mountain ranges adjacent to San Carlos de Bariloche. The trail follows a high-alpine path, connecting four distinct mountain refugios via ridgelines, loose scree slopes, and granite passes. The terrain is characterized by a mix of Andean forest and exposed high-altitude terrain, where route-finding and stability on loose rock are primary requirements. The system of stone huts (refugios) provides a logistical framework for the journey, though hikers must be prepared for sustained physical output in an exposed mountain environment.