When you arrive in Saint-Gengoux, you'll find several car parks close to the town centre. However, be careful, as the spots fill up quickly. For my part, I chose the (unpaved) car park next to the "Passage Saint Louis", which takes you into the medieval town.
(S/E) Go up "rue de l'Arquebuse" and turn left "chemin de Mont Goubot", you're on the GR®76. Go up this tarmac road, which turns into a path at the level of a house. Continue straight on until you reach a farm on your right.
(1) After the farm, follow the GR®76 through the undergrowth. Continue straight on along the GR®76 to the next marker. The path joins a road.
(2) At the Pertuis du Bois crossroads, follow the Culles-les-Roches signs (right towards Viaduc de Crainseny). You're now on the "Route de la Forêt". Follow this road past the village of Culles-les-Roches to the junction with the D153. At the crossroads, continue straight on, following the GR®.
(3) In the bend on your left, you'll see a small white sign with a pink dot. Follow this path, marked by pink paint on the trees, to the cave. Take the same path back down. At the end of the undergrowth, turn left and follow the GR®.
(4) You'll see the Saules cemetery on your right. Leave the GR® and walk along the vineyard so that you can turn right between the vines and pick up a path that leads to a cross (on the map, the path goes right up to the GR® but stops before it, separated by rocks and vegetation). At the cross turn left (on your right is a wash-house). At the entrance to Saules, turn right onto "rue des Miges" and you are now on a PR®. Follow this road to Saint-Boil.
(5) When you reach Saint-Boil, turn right onto "chemin de Noiseret". Follow this road to the school. At the school, turn right and follow the PR® signs to the signpost. At this sign, follow the signs for "Viaduc de Crainseny" straight ahead (turn right to "Moulin de Chatenay"). Follow this road to the Crainseny Viaduct.
(6) Take the wooden staircase to the right immediately after passing under the viaduct and follow this path up to the viaduct. After passing over the viaduct, continue straight ahead on this path through the undergrowth to the next crossroads.
(7) At the crossroads, turn right towards PR® Saint-Gengoux-le-National. Take this path through the undergrowth and follow the PR® markings (which are very well done and very present).
(8) When you reach a wider track, turn left following the PR®, which takes you downhill. At the end of the path, turn right, then left at the next crossroads (you're still on the PR®). Follow this path to the tarmac road which leads to a cross. At the crossroads, continue straight on Allée des Buis and at the crossroads, turn right to reach the car park (S/E).
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