Start from the car park near the Jean de la Fontaine school.
(S/E) Turn left onto Rue des Saussaies until you reach the roundabout.
(1) Turn right onto Avenue de la Forêt. Continue along the street until you reach the intersection with Allée Georges Bizet. There, take the stairs on the right at the top and take the path called "sente du battoir". At the end, take the path on the right that goes up into the forest. Continue along this path until you reach Carrefour des Picardes (2). Just after the crossroads, turn quickly left towards the north-west until you reach the Carrefour Corneille (3) star junction.
Leave the path on your left. There are two paths ahead; take the one opposite, which continues on from the one you arrived on (the one on the left, which is more winding, leads to the same place). Continue to the observatory.
(4) Cross the D2 with caution, turn left, go through the barrier. After 20 m, turn right, leaving one road in front of you and one on your right, and continue straight ahead on the road until you reach the Carrefour des Deux Amants.
(5) Take thethird path clockwise, almost opposite. Continue, leaving several paths on your left and right. The path turns north-west and arrives at another crossroads.
(6) Fork left after 150 m, down the slope.
(7) Turn left at the edge of the forest and join theGR®®2.
Alternative: descend to the next intersection and follow theGR®®2to the left.
(8) Follow it straight ahead, then take Chemin des Mareilles, then Chemin des Beauregards until you reach the junction with Rue des Bois.
(9) Cross it and follow Rue des Beauregards opposite until you reach the D2.
(10) Cross it and continue along Rue du Général Leclerc until you reach the junction with Rue d'Octave Mirbeau.
(11) Turn right onto this street, then left onto Rue des Biaunes.
(12) Turn left onto Rue des Temporets and follow it to the end.
(13) Go up Rue Saint-Marc on the left, towards the square, then turn right onto Rue du Puits. Take thefirst left (Sente des Perruches) and, at the top, turn right onto Rue des Saussaies.
(1) At the roundabout, continue straight ahead to return to the car park (S/E).