Louette and Chalouette between Étampes and Saint-Hilaire

Starting point and access: Saint-Martin d'Étampes station.
- RER - Line C, terminus of a section coming from Paris.
Take the only exit, Rue Salvador Allende, located on the only platform, and go down the stairs.

No signposts

(S/E) At the bottom of the stairs, turn right and go down a slope parallel to Rue Salvador Allende.

Red and yellow + yellow signage

At the "give way" sign, turn right into Rue de la Digue and go under the railway bridge. Follow the street as it winds through a residential area, ignoring the dead ends and side streets. Continue when the street becomes cobbled and narrower (watch out for oncoming cars) and you will come to a crossroads at the foot of Saint-Martin Church. Continue slightly to the left along Rue Braban until you reach an information sign on the right-hand side, walking alongside a lawn on your right.

No signposts

(1) Leave the church and its leaning bell tower on your right and continue straight ahead. At the end of the street, turn left onto Rue Badran. At the next intersection, turn right, still on Rue Badran. Pass by an old mill, whose water wheel can still be seen, and walk along the Chalouette on your left. At the T-junction, turn left and continue straight ahead at the stop sign. Take the^first right, Rue de Charpeaux. You will come back to the Chalouette. Follow it on your right, ignoring the footbridge that crosses it.

(2) When the street turns left and the river goes underground, continue straight ahead along a path alongside the buildings on the left. At the end, turn right, pass under a railway bridge and, at the crossroads immediately ahead, continue straight ahead along Chemin du Gué de Charpeaux. After about 30 metres, turn right and cross the Chalouette. Follow a tarmac track and ignore a turn-off on the left. Turn left with the track, following the Louette river on your right and fenced gardens on your left. The tarmac gives way to a path and the gardens to woods.

Red and yellow + yellow markings

(3) At a small bridge, turn left and enter the woods. Find the Chalouette and follow it on your left. Ignore a blue arrow that invites you to take a footbridge and continue through the woods and along the river. You will come out onto a small road.

No markings

(4) Follow the road to the left and pass in front of the Château de Valnay. At the stop sign, carefully cross the D21 and climb a small road that slopes diagonally to the right. You will come to a triangular intersection at the top (marker post on the left).

Blue markings

(5) Turn right. Walk west between the fields and along some copses.

(6) When the main path turns left between two copses, take a path on the right that is not marked on the map (be careful to spot this discreet start). Descend this shaded path. At the bottom, take the^second path on the right and climb up between the fields and then along the edge of the woods.

Yellow markings

(7) At the intersection at the top of the hill, continue straight ahead along the edge of the woods and pass under two power lines. Further on, descend, cross a small road and climb up the opposite side. Stay on the edge of the woods and then, on a slight descent, enter the woods. Come out onto a small road and follow it to the right, still descending. At a hairpin bend to the right, leave the road and, of the two paths that appear, take the one on the right, which is flat and bordered by a fence on the right-hand side.

Yellow + red and yellow markings

(8) At the next intersection, turn sharply right. At the T-junction, go left. Cross the Marette and pass a castle on your left. At the stop sign, turn right onto Rue Eudes Le Maire (D82). Just after a health centre on the right-hand side, turn left onto Sente de la Chalouette and cross the river again. You will come out at Place de l'Église. Turn right and you will immediately reach the church.

(9) With your back to the church gate, climb the cobbled lane opposite and then the steps leading to the cemetery. Go around the cemetery on the right, taking a path interspersed with steps.

Yellow markings

At the top (car park), turn right onto a discreet path (^PR®14) that winds between a field (on the left) and a property wall (on the right). At the end of the field, enter a wood and follow the wall on your right, which soon gives way to a fence. You will come out onto a small road.

Yellow + red and yellow markings

(10) Follow the road to the right and downhill. At the bottom, first turn right then left to cross the D82 (caution: narrow shoulders and limited visibility) and follow the D821 towards
Saint-Hilaire. Cross the Louette and continue straight ahead. Cross the Chemin des Cressionnères on the right-hand side and you will immediately reach a junction with the greenway (barrier on the right, small car park on the left).

(11) If you wish, you can make a return trip to see the remains of an old priory. Continue straight ahead on Rue de la Louette and after about 150 metres, turn left onto Rue du Prieuré. Cross Chemin des Hautes Terres on the left and you will immediately reach the old priory. Return the way you came.

Multiple signposting situations
Between points (11) and (14), the route follows a greenway for about 5.5 km, i.e. a tarmac path built on the platform of an old railway line (see recommendations in the practical information section). Unmarked sections alternate with marked sections where various combinations of yellow, blue, red and yellow are used. As the route is very simple and the signposting rather complex, the latter will only be mentioned when necessary.

(11) Go through the barrier to take the greenway (on the left if you are returning from the priory, on the right if you have not made the return trip). Walk alongside the old Saint-Hilaire-Chalo railway station and the watercress beds some distance to the right. Further on, ignore a path on the left and continue straight ahead on the greenway, still with watercress beds on the right. At a stop sign, cross a small road and continue on the greenway. Ignore a blue arrow that invites you to leave the greenway on the right and continue (with another blue marker) for about 300 m, until you reach an intersection (wooden posts).

(12) For those who wish to visit an old sandpit, turn left (blue sign), go through a chicane, cross the road carefully and walk through an area with information panels on the other side. Retrace your steps.

(12) Continue along the greenway, heading east, and pass under the power lines. After about 700 metres, you will reach another intersection: on the left, note a menhir in the garden of a private property.

(13) Continue east on the greenway. Cross two small roads, the^first at Vaujouan, the^second about 700 m further on. At the end of the greenway, go through a barrier and you will come out onto a street.

Blue + Yellow + Red and Yellow markings

(14) Then turn right and pass under the railway bridge.

Blue markings

Immediately turn left onto Boulevard Pasteur. Just after No. 44, turn right onto a path (chicane). Cross the Louette and continue along a street next to a school. At the end, turn left onto Rue Saint-Martin. Pass under the railway bridge and immediately turn right onto Rue Salvador Allende. You will soon see the Saint-Martin-d'Étampes train station on your right.

To return home:
- RER - Line C, towards Paris then Versailles and Saint-Quentin-en-Yvelines.

Train timetables: consult the Transilien website.

In wet weather, hiking boots are useful for the first part of the hike, up to point (7).

No water sources identified along the route.

Recommendations regarding the greenway:
The space is shared with various users (pedestrians, cyclists, etc.), who may be numerous on sunny days: caution and courtesy are required. In several places, the path is bordered on the right by paths or small roads that can also be used.

Alternatives:
Partial shortcut of the greenway - If you are concerned about the monotony of this straight, unwindy tarmac path, you can leave it and return south to the outward route, in particular: shortly before (12), following the blue markings to point (7), via Longuetoise; via the small road that connects Vaujouan to Valnay (4); via the small road that quickly leads to the point (3).
Return via Saint-Martin Church - After the end of the greenway (14) and after passing under the railway bridge, follow the yellow + red and yellow markings to the right and take a footpath. Continue following the markings via Rue Philéas Vassal, Carrefour Saint-Martin and Rue Courte. When you reach (1), turn left and follow the outward route in the opposite direction to the station.

The route is well marked for the most part. A detailed map is always useful (at least the one accompanying this description).

Hike completed by the author on 2 December 2021.

- Pleasant walks along the Chalouette and, for shorter distances, the Louette.
- Saint-Martin Church (12th-14th century). From the point (1), the entrance is on the right behind the bell tower. The tower leans, like the Tower of Pisa, due to subsidence during its construction in the 14th century.
- Badran Mill, shortly after (1).
- Valnay Castle (16th century) (4).
- Chalo-Saint-Mars Castle and Church.
- Remains of the Priory of Saint-Hilaire (12th century) (11).
- Watercress beds between (11) and (12). Watercress is an important market garden crop in the Essonne department, which is the leading producer in France.
- Former sandpit (12).
- Menhir known as La Pierrefitte (13), in a private garden but visible from the path.