From Massy to Saint-Cyr-l'École via the Bièvre Valley

Access: the starting point for the stage was set at Massy-Palaiseau station (RER B and C and Transilien V). It is entirely possible to start from Massy-Verrières station, which is closer to the GR® but less frequently served (RER B and C).

The entire route is marked in red and white.

(S) Leave Massy-Palaiseau station on the Vilmorin and Place de l'Union Européenne side (RER C / T12 side). At the bottom of the stairs, turn right and follow the railway tracks to the start of the Coulée Verte: take Avenue Raymond Aron, Avenue du Président Allende and Avenue des Martyrs de Soweto (following the reverse route of the end of the first stage). You will arrive at the crossroads with Avenue du Général De Gaulle, which comes from the right, and is very close to Massy-Verrières station.

(1) Take the Coulée Verte to the 19 March 1962 roundabout to rejoin the GR® 11.

(2) Go around the roundabout on the left until you reach Avenue d'Estienne d'Orves and take it towards Verrières-le-Buisson. Cross the Bièvre and continue straight on to Lake Verrières (a short detour off the GR®).

(3) Return to the Bièvre via Allée de la Garenne on the left, which joins the Bièvre valley road. Follow this road along the tree-lined side street until you reach the Moulin de Grais cultural centre.

(4) Leave the road and enter the adjoining woods, cross Rue de la Croix Pasquier and Rue de Paris to reach the fence of the Verrières golf course. Follow it on your left. This will take you to a branch of the river, which you follow upstream to the Monseigneur bridge (junction with the GR® 655, the Way of St James from Paris).

(5) Continue straight ahead until you reach the entrance to Igny station.

(6) Continue along the river until you reach Rue du Moulin.

(7) Cross the street by turning left and then right, and continue to a river retention basin, then pass under the N118 as you enter Bièvres.

(8) Just after the bridge under the N118, turn right, then immediately left, and head towards the centre of Bièvres at Rue du Petit Bièvres, still following a branch of the river.

(9) Take Rue du Petit Bièvres on the left, and immediately after Rue des Prés on the right. Continue along Chemin des Prés de Vauboyen, still following a branch of the Bièvre. Leave the town and continue between the river and the railway line, through the meadows, passing under the Château des Roches (Victor Hugo's literary home) to Vauboyen station, on the border of the Yvelines department.

(10) To avoid any uncertainty about the continuity of the GR® route from Vauboyen, temporarily leave the GR® by turning left, cross the level crossing and continue along the road to the cycle path that runs alongside the D117. Follow it to the entrance to Jouy-en-Josas. Turn right onto Rue du Val d'Enfer, cross the railway line again, then cross Square du Thabot if it is open, where you will find the GR® trail markings again.

(11) Return to Avenue Jean Jaurès and turn left onto Rue Oberkampf towards the town centre.

(12) Cross another level crossing, then turn right and cross Parc Oberkampf behind the station. Join Rue de la Libération (D446) on the other side, cross another level crossing in the other direction, and continue to the path that branches off to the left just after the roundabout.

(13) Take the path on the left and cross Parc de la Bièvre next to the Thalès University Campus until you reach Chemin de la Vallée. Take this path on the right until you reach Rue Charles De Gaulle (D446 again) at the Musée de la Toile de Jouy.

(14) Turn left onto Rue Charles de Gaulle and continue to the next station, Petit-Jouy-les-Loges. Turn left under the bridge.

(15) Continue along the road until you reach the path that runs alongside the Bièvre at its second crossing.

(16) Follow the river to the Vauptain stud farm. To avoid any ambiguity about the route, leave the GR® and continue straight ahead on the road to the foot of the Buc arcades at its northern end.

(17) From the north of the aqueduct, turn left along the arcades and reach their other end (where you will rejoin the GR® trail, which should arrive from the stud farm on the left).

(18) Cross the road and enter the woods opposite until you reach the centre of Buc, with its theatre, church and town hall.

(19) Continue along the river as you leave Buc until you reach the dyke of the Geneste pond, the first ofthe threeponds of La Minière.

(20) Climb onto the dyke and turn right to walk along the left bank of the pond. Continue along the river, turn right at the car park and then pass under the D91 before reaching the dyke of the Val d'Or pond.

(21) Follow the pond on its right bank along the path on the bank, or along the road just above it if the path is impassable or inaccessible (muddy in wet weather). Continue along this path to the next dyke, that of the Moulin au Renard pond. Cross it to return to the left bank.

(22) Continue along the bank to the end of the small cove.

(23) Leave the Bièvre valley by taking the path that goes up along the Ru du Bois Robert. Follow this path, which turns right when you reach the N12. Walk along it for a short while, then cross it above a tunnel.

(24) Leave the GR® trail on the left in the woods and turn right to reach Saint-Cyr station. To do this, follow Rue Francisco Ferrer straight ahead until you reach a steep downhill slope that leads to the railway tracks. Reach Saint-Cyr station, the entrance to which is located on the other side of the bridge under the railway tracks (E).

Note: Saint-Cyr station is on the Paris-Montparnasse network.

This stage features many dirt paths in the forest. Be sure to bring suitable equipment (good walking shoes). There are no particular difficulties (especially with the option of reaching a station along the way to break the stage into several parts), except for a continuous, almost imperceptible false flat, but some sections may be muddy or even frozen in winter.

(S) Departure from Massy-Palaiseau station in Massy, which is very well served: TGV, Ouigo, Transilien V for Versailles, RER B and C for Paris, tram for Évry, numerous buses. Another possible departure point is Massy-Verrières station, which is closer to the GR® but only served by the RER B and C.

Between Massy and Les Loges-en-Josas, the GR® route closely follows the Grande Ceinture railway line used by the Transilien Massy-Palaiseau <-> Versailles-Chantiers line V. All the intermediate stations, generally served by a train every half hour in each direction, are very close to the GR® and therefore very easily accessible. It is therefore possible to complete the stage in several stages by stopping at one of these stations, with Jouy-en-Josas station being the one that allows you to split the stage in two as evenly as possible.

(E) The Saint-Cyr station, reached at the end of the stage, is also frequently served by the RER C and Transilien N and U lines, on the common trunk of the Montparnasse network (at least three trains per hour in each direction). It provides easy access to the nearby Versailles-Chantiers station (5 minutes away), as well as further afield to central Paris (Montparnasse, Invalides, etc.) and La Défense.

Hike completed on 21 January 2024 (when some sections of the GR® were frozen) with the aim of covering the entire GR® 11.

• Lac de Verrières (3)
• French Museum of Photography in Bièvres, on the right at (9)
• Victor Hugo's literary house (Château des Roches) in Bièvres, between (9) and (10)
• Musée de la Toile de Jouy in Jouy-en-Josas (14)
• Arcades of Buc, between (17) and (18)
• Churches of Igny (left at (7)), Bièvres (right at (9)), Jouy-en-Josas (left at (12)) and Buc (19)
• La Minière ponds in the upper Bièvre valley and the Versailles forest, from (21) to (23)