Depart from the Carrefour des Faisans car park on the edge of the D446 in the Rougeau Forest.
(S/E) With the D446 in front of you, head towards it and take the tarmac road on the left, which runs parallel to it. Immediately afterwards, turn left (due east) onto the wide road called Route de Corbeil. Follow it straight ahead until you reach the Carrefour du Grand Veneur.
(1) At Carrefour du Grand Veneur, follow Route de la Grange, the third road on the left.
(2) After about 250 metres, at a pond, turn left onto the Sentier des Mares, marked in yellow. Follow this path (which is quite wide despite its name), which is very well marked. If the rainfall in the previous days and months has been sufficient, you will see four ponds (these ponds are not always full of water). Go around the fifth pond on the right, which is crossed by a wooden bridge (for observing the flora and fauna) that you do not need to cross.
(3) At the end of the path, turn right onto the tarmac Route du Débouché de Sénart. After about 100 metres, cross the Route Forestière Tournante (forest houses on the right) and take the path opposite, still marked in yellow. Leave the forest and you will come to a small canal.
(4) Turn right and follow this canal along the path on its left bank. At the end, cross the road (Avenue des Regalles) and follow another canal on your right along a path and then Rue des Marronniers. Please note that the yellow markings are not entirely reliable in this area, in particular as a bridge has been removed.
(5) Take the first bridge on the right, then immediately turn right onto Rue du Canal, which runs alongside it in the other direction. When this street turns right to cross the canal, leave it and continue along a path that runs alongside the canal on your right. At the end, turn right, then immediately left onto Avenue des Regalles. Pass in front of a secondary school. The avenue is bordered on the other side by the walls of the Château de la Grange-la-Prévôté park.
(6) After the secondary school, cross the avenue to go through the castle gates (if the gates are closed - especially on Mondays - walk along the walls, arrive at the crossroads with Avenue du 8 mai 1945 and continue the detour by taking this road on the right to find yourself in front of the main entrance gates).
Ignore the yellow markings. Follow the path, pass the technical buildings and then the front of the castle, turn left and take the path towards the main entrance gates.
(7) Once you have passed through the main entrance gates, follow Avenue du 8 mai 1945 on the right, which runs alongside the Écuries de la Prévôté. Take the first lane on the right towards the forest. This is Route de la Grange; follow it for about 600 metres.
(8) Please note that after 600 metres, follow the road that veers to the left (do not continue straight ahead). Cross the Carrefour de la Grange and continue straight ahead on the road of the same name.
(2) From the start of the Sentier des Mares, go straight ahead to the Carrefour du Grand-Veneur.
(1) Then take the third right, the Route de Corbeil, which you took on the way there. This will take you back to the car park where you started (S/E).