Park at the Vions car park.
(S/E) Head east and descend the road. When the road turns right, take a path on the left that descends through the woods towards the Saut du Doubs. Return to the road and follow it to the right for about 250 metres.
(1) Leave the path opposite, which will be used for the return journey, and continue downhill to the right along the road.
(2) At a hairpin bend to the right, leave the road and take thesecond path on the left (after possibly making a quick return trip to admire the Saut du Doubs). Then take the footbridge to cross the Doubs and the border. N.B. Crossing is tolerated for hikers, provided they carry identity documents.
(3) At the end of the footbridge, follow a forest path to the left. Further on, leave the path leading to the waterfall on your left.
(4) At the intersection of three paths or trails, take the middle one (leaving the path on the far left and the forest trail going up to the right). The path gradually approaches the lake shore.
(5) Walk along the lake on your left for about 2 km, sometimes passing through tunnels dug into the rock.
(6) At an intersection (be careful, it is not necessarily obvious), continue along the main path that climbs to the right through the woods. Join a carriageway and follow it to the left. Descend towards the Châtelot dam.
(7) At the dam, take the tunnel. Continue on the path that begins to descend towards the Doubs. Make two hairpin bends, one to the left and then one to the right.
(8) At the next hairpin bend (to the left), continue straight on towards Le Châtelot. You will reach the few houses that make up this hamlet.
(9) Immediately turn left onto the path leading down to the Doubs, known as Ruelle de la Truite. Ford the Doubs, first using the stepping stones, then the rock forming a natural dam and finally the small blocks of stone placed there for walkers. Then climb a small ladder.
(10) Turn left and follow the river to the dam.
(11) At the intersection, continue straight ahead to pass the dam (do not take the stairs on the right). Continue for about 3.5 km on the path that runs alongside the Doubs, ignoring all the paths on the right.
(12) At the Saut du Doubs (viewpoint), turn sharply right onto a path that goes uphill. Ignore a path coming from the right. At the next junction, turn left and return to the tarmac road you took on the way there.
(1) Follow the road to the right. After about 250 m, turn right onto the path. Return to the road and follow it to the Vions car park (S/E).