The starting point is in front of the church in Grand Serre, a small village on the border between the departments of Isère and Drôme.
(S/E) Set off eastwards along the Grande Rue, past the church. You’ll pass the very pretty old market halls. Turn right onto the first street leading down into the valley (Rue Saint-Antoine). A little further on, it becomes the “Route de la Roche” and, once in the valley, it leads to a “Stop” sign at the D51. Turn left, then take the first small road on the right (Route de l’Étang).
(1) You’ll come to a ford. You can, however, take the bridge on the left rather than getting your shoes wet. Ignore the road branching off to the right by the recycling bins. The road begins to climb. You’ll pass a cluster of houses on the Saône. Ignore the road branching off to the right towards a spa. At a second cluster of houses, carry on straight ahead. The tarmac gives way to a good stony track.
You enter the forest.
(2) On your right, you come to another wide track; take this one. There is a wire fence on your right. You then take the first track on your left.
(3) When you reach a crossroads, head slightly uphill to the left. You’ll skirt a field before quickly returning to the woodland. You’ll skirt a meadow before heading back into the woodland again. You’ll emerge onto a very wide gravel track (it was built to install the wind turbines).
(4) Turn right onto it. You’ll pass alongside or underneath a wind turbine (it’s quite impressive...). Continue along this track, which, after a while, is tarmac-surfaced across half its width.
(5) There’s a lovely little pond on your left, by the side of the road. Carry on until you come out onto a small county road.
(6) Turn right, but leave this road very quickly to join a track, also on the right. The track becomes rather rough, rutted by machinery. Carry on along it. At the first Fork in the road, turn right. At the second, turn left. You’ll come to a small road (Route de Saint-Christophe). Take it to the right.
(7) Very soon, you’ll see two paths branching off simultaneously on your left. Take the second one (marked with yellow and red signs). Ignore a wide path coming in from the left.
(8) After quite a while, you’ll come to a track which you take on the left. Follow it for quite a while. It turns into a tarmac road (it’s a common occurrence…). You’ll emerge onto a small road.
(9) Turn left. The small road curves naturally to the right.
(10) On your left, you’ll see a sign: Bonne Combe – 408m. Take the grassy path opposite (i.e. to the right as you approach). Follow it for a while until you come out onto a small road
(11) Turn right and, a few metres further on, continue to the left.
(12) You’ll come to thesecond ford across the Galaure. If the river is in flood, there’s a footbridge on the left. You’ll reach a county road (Route de Roybon).
(13) Cross it and take the small road opposite that goes uphill, keeping slightly to the right. Pass a private track and take another small road, again keeping to the right.
(14) You are now at a place known as the “Labyrinthe de Hauterives”. Continue along the hillside for a good while before coming out onto a small departmental road.
(15) Turn right. __ Be careful!!! Traffic moves quite fast._
If there are several of you, walk in single file and, unless otherwise indicated, keep to the left-hand side of the road, facing oncoming traffic.
After about 1 km and a fairly steep climb, you’ll enter Le Grand Serre and thus return to your starting point (S/E).