Park at the car park at the Canche aux Mercers (from Arbonne-la-Forêt, take Route d’Achères-la-Forêt - D64; after a kilometre and a sharp turn left, take a small road on the right, go under the motorway leading to the car park).
Blue markings
This hike follows the Denecourt-Colinet trail No. 16, in Blue on the IGN map. Markings are dense with very clear indications on the ground (signs indicating variants in particular). Nevertheless, there are few passages where you have to be careful not to lose the route.
(S) At the end of the car park, take the path due west. Quickly reach the junction of the two branches of the circuit, heading south and north (sign). Follow the left branch towards the west. The path winds through the woods while remaining parallel to a wide path some distance to the left. Cross a short sandy area with some rocks and then continue through the woods. The trail, which becomes “carved" into the sandy soil, stands in open field (clear signs of an old forest fire). Return to the the underwood and continue to the west.
(1) Continue westward through the woods. The path veers to the south to then reach a wider path (Chemin de la Charme). Cross the road, continue south slightly uphill and reach a ledge lined with many rocks, where you can enjoy a beautiful view (junction with the circuit of the 25 bumps (25 Bosses), marked in Red).
(2) Do not follow the Red markings, but head right at acute angle on the trail marked in Blue. Continue west. The trail descends turning right, crosses another path to then go up opposite (north).
(3) Continue to the west. The path mostly runs along the plateau edge, with beautiful views on the left. The trail takes a west-northwesterly direction, it goes up and down in the middle of a large cluster of sandstone boulders the size of paving slabs (old quarries).
(4) The trail turns right to the north and begins a descent into the Gorge aux Chats. After crossing several perpendicular paths, head up steeply. The trail turns left and makes a hairpin on the right.
(5) It is on the north branch of the circuit and the trail takes a generally east orientation. Remaining at an almost constant altitude, ignore some trails heading to the left. After a pronounced bend on the right, the trail leaves the plateau to lead to a clear area of heathland on platières (the Laris).
(6) Continue on the moor and back north along the edge of the plateau. Walk due east to a viewpoint (in front of the stone building slightly to the right is the water of the Loing, noted on the IGN map).
(7) Do not move away from the edge of the board (it is possible to confuse this with the 16-16 shortcut, which turns south), but instead continue to the east. Head down over a short distance, cross a path and head up opposite. South-east oriented, the trail alternates short climbs and descents, passing by some boulders.
(8) The trail turns left and goes down steeply. At the bottom of the descent, turn right and ignore a path on the left towards the car park of the Feuillardière. Soon after, back on the right. The trail continues up amidst the boulders. Continue eastward. Head down to reach the Loing aqueduct facilities and head round it to orient yourself south. After turning left, the trail makes a final short climb and then head down and join the south branch of the circuit taken at the start of the hike. Turn left onto this road to quickly reach the starting point.