Start at Place de l'Église in Brueil-en-Vexin. There is a small car park where you can park.
(S/E) From the car park, walk downhill and follow Rue de l'Église on your left. At the T-junction, turn right onto Rue du Pont Madame. Walk past a castle and cross the Montcient river. At the T-junction, turn left and follow Rue du Vexin for about 100 metres.
(1) Leave the street and turn right onto Chemin de la Cave aux Fées (alley), then immediately take a path on the left. At the foot of a group of trees on the left is the Cave aux Fées (information sign).
(2) Continue along the path heading north-west, then north, ignoring the perpendicular paths. You will arrive at Maigremont.
(3) Follow a small road on the left, which soon becomes a path. Take the first path on the left (after about 200 metres). Continue south-west until you reach the entrance to the village of Sailly, just after a rudimentary football pitch on the right.
(4) At the crossroads, turn right onto Rue du Cornouiller. Cross Impasse du Mont Roty and, at the next crossroads, turn left onto Rue des Bonnes Joies, which descends towards the centre of the village. Ignore a small lane on the right and, at the next crossroads, turn right.
(5) Cross the D130 road and cross the Montcient again. At the next crossroads, turn left onto Rue Saint-Laurent. Cross Route de Vetheuil and follow the road that leads to the cemetery (follow the signs; do not take the road on the far right). Pass the cemetery and continue along the path that extends the street. Follow a large pond on your left and a poultry farm. Follow the path to the houses on the edge of Brueil-en-Vexin.
(6) Continue east-southeast on Rue de la Carrière. Ignore the first path on the right after a few metres. At the fork, take the path on the right that leads through the forest. At the T-junction (hangar on the right), turn right. Cross the tarmac road and continue along the path (south-west then south). After about 700m, you will reach a farm (La Malmaison).
(7) At the fork, follow the left-hand road (east). At the crossroads at the edge of the forest, turn left and go downhill to a larger road, the D130. Cross this road and take the path directly opposite.
Head east, pass a group of buildings on your right and reach the corner of a wood.
(8) Then turn left and, 200 metres further on, left again. Follow the path that descends gently between the fields to the entrance to Brueil-en-Vexin.
(9) At the crossroads, turn right onto the D130 road which leads to the village. Ignore the first street on the left and turn left into the next one, Rue de l'Église. Continue to the church and its car park (S/E).