Janvry Fountain – Fauvettes Viaduct loop from Briis-sous-Forges

Janvry Fountain – Fauvettes Viaduct loop from Briis-sous-Forges

Hard

riders

Janvry Fountain – Fauvettes Viaduct loop from Briis-sous-Forges

02:48

43.7km

490m

Gravel riding

Hard gravel ride. Very good fitness required. You may need to push your bike for some segments of this route. The starting point of the route is accessible with public transport.

Last updated: October 7, 2026

Tips

Includes a segment that is highly dangerous

A part of this route comprises highly technical, difficult, or hazardous terrain. Specialist equipment and prior experience is required.

After 28.8 km for 75 m

Waypoints

Start point

Bus stop

Get Directions

3.71 km

Janvry Fountain

Highlight • Castle

Nice little village to see

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3.87 km

Janvry Castle

Highlight • Castle

Private castle; a pretty alley leads there.

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9.53 km

Fauvettes Viaduct

Highlight • Bridge

Magnificent viewpoint over the valley surrounded by greenery, accessible by "gravel" paths (roots and stones) through the wood or by "hiking / mountain biking" trails in the valley (it will …

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10.1 km

Like the nearby Fauvettes viaduct, the Montjay tunnel once served as the old Paris-Chartres railway line. In the middle of the communal forest of Bures-sur-Yvette, it punctuates the straight and rolling line leading to the viaduct.

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19.3 km

Villiers-le-Bâcle Hill

Highlight (Segment) • Forest

The coast of the debacle :)

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28.8 km

Stone Arch Bridge on the Old Railway Line

Highlight • Bridge

Super atypical passage, I recommend

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30.0 km

Tour in the woods...

Highlight • Other

30.6 km

Boullay-les-Troux Climb

Highlight • Climb

Nice climb in the shade, little traffic, medium tar if very thin tire (<25 mm)

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43.7 km

End point

Bus stop

Way Types & Surfaces

Way Types

13.9 km

12.8 km

6.14 km

5.77 km

5.04 km

119 m

Surfaces

21.1 km

10.5 km

7.60 km

4.12 km

276 m

210 m

Elevation

Nothing selected – click and drag below to see the stats for a specific part of the route.

Highest point (180 m)

Lowest point (60 m)

Weather

Wednesday 21 October

16°C

7°C

67 %

Additional weather tips

Max wind speed: 25.0 km/h

to get more detailed weather forecasts along your route

Comments

September 28, 2023,GRVL cool

GRVL route without great difficulty on rolling paths. Passing through Briis/Forges, do not hesitate to take a detour via the Anne Boleyn tower.

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May 23, 2024,GRVL en vallée de Chevreuse

For information on spring fava beans:
Although the wild variety of faba bean is not really identified, it is assumed that it originated on the shores of the Caspian Sea. First consumed by humans since the Neolithic period as a vegetable in the Middle East, the spring bean is today cultivated throughout France, both at the head of the crop …

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