Routes Planner Features Updates

Login or Signup

Login or Signup

Login or Signup

Mountain biking trails

Arzal Dam – Old Port of La Roche-Bernard loop from Billiers

Mountain biking trails

Arzal Dam – Old Port of La Roche-Bernard loop from Billiers

Moderate

4.2

(13)

130

riders

Arzal Dam – Old Port of La Roche-Bernard loop from Billiers

03:41

49.1km

460m

Mountain biking

Moderate mountain bike ride. Good fitness required. Suitable for all skill levels. The starting point of the route is right next to a parking lot.

Last updated: September 24, 2026

Tips

Includes segments that go up or down a series of steps

You may need to carry your bike.

After 29.7 km for 8 m

After 29.8 km for 42 m

Waypoints

A

Start point

Parking

1

13.7 km

Arzal Dam

Highlight • Monument

Built in 1970, the Arzal dam allows the regulation of the waters of the Vilaine and the storage of drinking water for the inhabitants of the region. Its construction allowed …

Translated by Google •

Tip by

2

18.1 km

Very nice path

Highlight • Other

3

21.0 km

Vilaine Riverside

Highlight • River

4

24.7 km

Villaine Valley

Highlight • River

Very nice passage despite the luggage on our gravels. A beautiful trail.

Translated by Google •

Tip by

5

27.5 km

Old Port of La Roche-Bernard

Highlight • Settlement

The stones, weathered by time, and the steep alleyways tell the story of this "Small Town of Character," born of the sea and maritime trade. Clinging to the banks of …

Translated by Google •

Tip by

6

34.1 km

Gaillard Footbridge

Highlight • Bridge

GR349 crossing point

Translated by Google •

Tip by

B

49.1 km

End point

Parking

Way Types & Surfaces

Way Types

25.8 km

10.4 km

4.63 km

4.24 km

3.39 km

729 m

< 100 m

Surfaces

19.9 km

10.4 km

6.63 km

5.58 km

5.32 km

1.28 km

Sign up to see more specific route details

Sign up for free

Elevation

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

Sign up to see more specific route details

Sign up for free

Weather

Powered by Foreca

Saturday 10 October

17°C

7°C

64 %

Additional weather tips

Max wind speed: 15.0 km/h

to get more detailed weather forecasts along your route

Comments

Want to know more?

Sign up for a free komoot account to join the conversation.

Sign up for free

Our route recommendations are based on thousands of hikes, rides, and runs completed by other people on komoot.

Navigate Send to Phone

Move start point

Embed on a website

Report an Issue

Report restricted access

Nearby routes

4.7

186

Arzal Dam – Old Bridge loop from Nivillac

02:58h

38.4km

450m

4.6

186

Old Port of La Roche-Bernard – Arzal Dam loop from Arzal

02:35h

34.4km

390m

4.5

134

Port-Blanc Beach – Port of Crouesty loop from Sarzeau

02:32h

43.1km

220m

4.7

150

Conleau Beach – Port-Anna Harbor loop from Domino's

02:41h

44.1km

190m

4.6

137

Old Port of La Roche-Bernard – Bridge tour loop from La Roche-Bernard

02:54h

36.2km

460m

4.4

106

Bridge tour – Superb light loop from École primaire privée Sainte-Thérèse

02:09h

27.5km

290m

4.4

192

Le Guérandais – Le Croisic loop from La Turballe

02:45h

52.6km

170m

4.8

115

Le Guérandais – Le Croisic loop from La Turballe

01:54h

37.6km

80m

4.5

111

Saint-Laurent Chapel – Theix-Conleau-Saint Armel loop from Séné

02:05h

34.8km

140m

4.5

113

Folleux Lodgepole Pine – Port de Folleux loop from Péaule

03:34h

43.1km

560m

4.6

81

Suscinio Castle – View of Château de Suscinio loop from Le Cossay

02:31h

42.2km

200m

4.3

100

Conleau Island – Conleau Beach loop from Theix-Noyalo

02:34h

43.6km

190m