Réserve de biosphère de Fontainebleau et du Gâtinais, Île-de-France, France
8.6 miles (13.8 km) · 1,602 ft elevation gain · Loop · trail · Route
Sentier des 25 bosses is a 8.6-mile loop route in Réserve de biosphère de Fontainebleau et du Gâtinais, Île-de-France, France, gaining 1,602 feet of elevation. The route follows a valley-shaped elevation profile. The terrain covers 4 distinct sections with no major climbs. About 63% of the terrain is runnable, with significant hiking sections. The route opens with mixed terrain and finishes with flat terrain.
| Distance | 8.6 mi (13.8 km) |
| Elevation gain | 1,602 ft (488 m) |
| Average gain | 187 ft per mile (35 m per km) |
| Longest climb | 2.6 mi, 151 ft of gain |
| Steepest climb grade | 25.6% |
| Runnable | 63% of the route |
| Climbs / descents | 0 climbs, 0 descents |
| Profile shape | Down, then up |
| Difficulty score | 8.1 of 100 |
| Surface | trail |
| Route shape | Loop |
| Type | Route |
| Grade band | Share of route |
|---|---|
| Flat | 37% |
| Mild uphill | 10% |
| Moderate uphill | 9% |
| Steep uphill | 13% |
| Mild downhill | 7% |
| Moderate downhill | 9% |
| Steep downhill | 15% |
Sentier des 25 bosses has 1,602 ft (488 m) of elevation gain over 8.6 miles (13.8 km). That averages 187 ft of gain per mile.
The difficulty score for Sentier des 25 bosses is 8.1 of 100. That is harder than 61% of routes at a similar distance. About 63% of the route is runnable at typical trail effort; the rest is steep enough that most runners hike.
The longest climb on Sentier des 25 bosses runs 2.6 miles (4.2 km) and gains 151 ft (46 m). The steepest climb grade on the route is 25.6%.
Preview this trail in 3D flyover, view the elevation profile, and explore the segment breakdown.
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