From the D116 at the eastern exit of Sainte-Mesme, take the small road under the railway line towards Corbreuse. The entrance to the track is just after that, on the right as you go uphill, and there are a few parking spaces at the start.
(S/E) Follow the track. After about 300 m, pass a path on your right which can take you back to Sainte-Mesme via the Moulin Corpeau, and carry on straight ahead.
(1) Turn left onto a path that climbs gradually through the woods.
(2) Once at the top, the path winds along the edge of the slope and eventually joins a wider track.
(3) Turn right and carry on to the Queue d’Auneau forest track.
(4) Turn right, leave the forest and head along the edge of the woodland before reaching the open countryside. Ignore the straight path on the left leading to Corbreuse and carry on straight ahead until you reach a junction.
(5) Turn right and take the small tarmac road towards the Brandelles farm.
(6) When you reach the farm, take the path that runs alongside it on the right, then heads downhill, skirting a pasture on your right.
(7) At the bottom of the descent, continue to your right, with the River Orge a few metres to your left. The path follows the valley, with properties and ponds more or less visible on the left. At a place called Le Gué d’Orge, you’ll come to a small tarmac road which you should follow to the bridge and the ford over the River Orge.
(8) Do not cross the river here, but take the small forest track sharply to the right, then continue down the valley until you reach the fork where you started.
(1) Carry on straight ahead to reach the car park (S/E).