Starting point: the Mail du Pré Romain car park (Salle du Pré Romain). Access is via the D45, Route de Flexanville.
(S/E) On leaving the car park, head up to the right for 100 metres and cross the D45 opposite the tennis courts to take a wide path between two hedges. Walk past a sewage treatment plant, cross a stream and continue to a T-junction.
(1) Turn right. A little further on, cross the D42 with care. Pass a manhole cover for the Avre aqueduct on your left and carry on for about a hundred metres.
(2) At the junction, just before a ditch, turn left (hedge on your right). Carry on until you reach a small road.
(3) First turn left then right to cross the road and take a path marked in yellow through a wood (fence on your right). At the end of the path, you’ll come to a tarmac road; continue to the right along Rue de la Tuilerie. After a left-hand bend, you’ll reach a junction.
(4) Turn right and cross the bridge over the railway line. Just off the bridge, turn left and walk through the hamlet of La Masse. At the Fork in the road at the end of the tarmac road, take the path on the right and continue straight on to the Étang de la Pimardière, ignoring any side paths.
(5) At the crossroads, head straight ahead to walk round the pond in a clockwise direction, keeping as close to the water as possible. Further on, at the north-west corner of the pond, go through a green metal gate and continue to the right.
(6) At the fork in the path, which you’ll reach shortly, turn left, passing through another wooden gate. Stay on the wide path, cross a junction of tracks and, further on, ignore a path branching off to the left before reaching the next junction.
(7) Head down to the left along the main path, which very quickly joins aGR®® (red and white markings on a tree). Follow it to the right and carry on straight ahead. Join Rue du Clos aux Biches and follow it straight ahead. At the end of the street, climb the footbridge over the railway line.
(8) Leave Orgerus-Béhoust station through a small gate and turn right onto Rue de la Gare. At the T-junction, turn left and walk past the church.
(9) Cross Rue du Moutier and continue straight ahead into Impasse du Moutier, then onto the path that runs from it. At the end of this path, turn left towards the railway line. Then head right, keeping the aqueduct on your right and the railway line on your left. Cross a small road and continue to follow the aqueduct for about 500 metres.
(10) At the junction, turn right onto a small grassy path towards a thatched cottage and you’ll come out onto Chemin de Bazainville. Further on, cross Rue du Clos des Bourgognes and take Rue des Agneaux as far as the cemetery. Then turn right onto Rue du Bois Carré.
(11) At the end, turn right onto Rue du Pressoir. At the roundabout, continue left onto Rue du Stade Marcel Cuaz. Then first turn right then left to cross Place des Halles towards the Town Hall. Walk past the Town Hall on the right and carry straight on to the start via Route de Flexanville (S/E).


