Vieille Roche Route

Park in the car park on the south bank of the dam, before the barrier leading to the harbour.

:/A: Take the path running along the upstream side of the dam to the lock. On the right, the vast body of water created by the dam serves as a boat mooring area, stretching as far as the Drézet water treatment plant (white buildings in the background, on the hillside).

(1) If you’re lucky enough to arrive at the lock whilst the bridge is raised, do take the time to watch the pleasure boaters manoeuvring under the guidance of the lock keeper. When it’s busy, it can be quite a spectacle!
Head back towards the car park by following the downstream side of the dam. The atmosphere changes here: on this side, the influence of the sea is palpable, with the ebb and flow of the tides and the salty sea air. An interpretive trail allows you to explore the dam and its impact on life along the maritime stretch of the Vilaine.
Head up to the upper car park (beyond the harbour barrier) and take the path that starts at the far end. Follow it to Chemin de la Cayenne, turn right, cross the road leading to the dam, and continue straight on until you reach the first houses.

(2) At the entrance to the village, take the road straight ahead and follow it up to Le Bossenno. It is a quiet, tree-lined road, but there is still some traffic. So please take care on this stretch.

(3) At Bossenno, the road curves in an S-shape. At the entrance to the second bend, leave the road and continue along the track that winds between two tree-lined embankments. After 400m, it opens out onto a small access road to a property, which leads to the village of Camoël. After a right-hand bend, take the street on the left, then turn right into Rue de l’École. Walk past the school and reach the church forecourt by going round the north side of the church.

(4) From the church, head towards the departmental road (D34), cross it and head opposite towards the town hall. Follow the road (D139) leading towards Assérac until you reach the Route du Pontrel. A footpath runs alongside the road up to this junction.

(5) Take the main path on the left which leads into the woods. At the first junction, turn left until you reach the next junction, then turn right, then left to head back up towards Ville Neuve. Once past this hamlet, and after a wide bend, take the path branching off to the right at the three-way junction. Take the first path on the right leading to Le Grazo. At the road, turn right then left to pass between the houses.

(6) Beyond the village, continue along a narrow path between two hedgerows which leads onto a wide, carriageable track. Turn left until you reach the first road, cross it, keeping the mill on your left, and continue between some old farm buildings until you reach a dirt track. After 170m, cross the departmental road (D34) with care, and turn onto the Route de Vieille Roche, leaving La Chaumière on your right.

(7) This thatched cottage is a nightclub; walk round it to take a wide path on the right-hand side of the road. Do not take the path that runs directly behind the thatched cottage, but the one that branches off at right angles. Follow it to the second junction, then take the small road furthest to the left, which leads to the entrance to the village of Le Gastre. Turn right, then left twice, heading towards the far end of the village.

(8) Leave the houses via the path heading north, towards the Vilaine. At the first junction, turn left onto the path that descends into a valley and follow it to the riverbank.

(9) After a steep climb, you’ll reach the riverbank; follow the path along it as far as the edge of the marina. A sloping path leads down to a side channel, which you cross via a footbridge. On the opposite bank, follow the footpath running parallel to the access road to the car parks and jetties until you return to the car park where you started. One last short, steep climb, and you’re back at the start at the southern entrance to the dam (S/E).

The circular route can be shortened by one kilometre if you do not walk the round trip along the dam’s embankment. Alternatively, this section can be covered on the return journey.

Shops and refreshments are available at the dam, on the Arzal side.

The operation of the dam’s sluice gate requires the bridge to be raised, which means the road is closed, including to pedestrians. If you’re crossing to the other bank, be mindful of the timings, otherwise you might be stuck there for a while. In summer, the closure can last up to 45 minutes.

During wet weather, the path between points 3 and 4 may be cut off by large puddles. If it is not possible to go round them via the neighbouring farmland, head for Camoël via the Kerguen road.
Similarly, the route between Le Pontrel (point 5) and Villeneuve may be cut off when the Noë des Mouches stream bursts its banks. In this case, it is best to head for Le Grazo from the village of Camoël, taking the small streets and paths to the south of the RD 34.

There is a fish ladder on the dam, designed to help migratory fish (eels, in particular) swim upstream. It is open to visitors. For further information, please contact the harbour master’s office on the Arzal side.

Whilst in Camoël, do pop into the church. It has a special atmosphere, to which the painted walls of the transept contribute greatly.