From Sucy-en-Brie to Boissy through the forests of Notre-Dame and Grosbois

Starting point and access: Sucy-Bonneuil station.
- RER - Line A, on the section between Paris and Boissy-Saint-Léger.
Take exit 1, Place de la Gare.

Red and yellow + yellow markings

(S) Upon exiting the station, cross one street, then cross Square Charles de Gaulle diagonally to the left. At the end, turn right onto Rue de Montaleau towards the gymnasium of the same name. Climb gently and, at^{the first} intersection, continue straight ahead. At^{the second} intersection, turn left onto Rue de Sévigné. At the end, turn right.

(1) After about 30 metres, turn left onto Sentier du Vieux Val. Follow this gravel path that winds between walls and garden fences. At the end, at a T-junction, turn left. You will quickly come to a busy street; follow it to the right on the right-hand pavement. At the traffic lights, turn left, cross the road at the pedestrian crossing and first turn right then left to take Rue Raspail downhill.

Red and yellow markings

Cross Rue Thiers and continue downhill on a path between fences. After a left turn, you will come out onto Rue Chevreul. Follow it to the right. Cross Boulevard Pierre Raunet on the left, then Rue de la Ferme on the right, and turn left, still on Rue Chevreul. You will reach the shore of a small lake.

(2) Turn right at an acute angle and follow the lake on your left. Pass a chicane (you can make a very quick return trip to a small island) and continue along the lake. Pass another chicane, reach the end of the lake and cross the street at the pedestrian crossing.

No signposts

Ignore the arrow indicating a right turn (which leads to a detour that is not worth taking) and take the cement path opposite, which soon gives way to a staircase.

Red and yellow + yellow signposts

Come out onto a path and follow it to the left. Cross a river and go up the other side.

(3) At the top, turn right to enter Morbras Park. Leave a few small brick buildings on your left and follow a wide paved path. Pass the reception building and go straight ahead at the next crossroads. Stay on the path that winds between tree-lined lawns. Walk along a limestone lawn (information board) then, at a small crossroads (central tree), ignore the path that climbs up to the left and continue along the main lane. Climb up and leave the park. Cross a car park, then turn right and walk down a street.

Red and yellow markings

At the bottom, cross the street at the pedestrian crossing and look for another pedestrian crossing a little further on to cross a wide avenue.

(4) Follow the avenue to the right, keeping to the well-marked pavement on the left. Cross a river and continue straight ahead. At the entrance to Sucy, turn left towards Noiseau. After about 50 metres, before the sign for Noiseau, cross the road at the pedestrian crossing, go through a chicane and take the path opposite that leads into the woods. Follow a stream on your left and leave the woods.

(5) Follow a wide grassy lane, keeping a house clearly visible on your right. At the junction that quickly appears, continue straight ahead. Stay in the grassy corridor (green corridor) between a narrow wooded area on the left and gardens on the right. Ignore the paths and footbridges on either side.

(6) At the end of the green corridor, continue straight ahead and enter a wood. Leave the wood and turn left, keeping a lawn on your right. Cross the D 136 at the pedestrian crossing, on the border between Noiseau and Sucy, and enter the Forêt Domaniale de Notre-Dame via the Chemin de la Gueule Noire. Continue straight ahead on this wide, stable path, ignoring all the paths on either side, until you reach a large crossroads (information sign).

Red and yellow + red and white + green markings

(7) Then take the^first path on the right, which is rather inconspicuous (signpost), and head south. At a three-way junction, turn right and walk alongside the houses on your left. Pass through a forest gate and you will come to a roundabout. Take the^second road on the left, Boulevard de la Liberté. Continue straight ahead, cross several streets and note a modern chapel on the left.

Red, green and yellow markings

(8) At the end, turn right and follow a mini-market. When the street turns left, go through a gate and continue straight ahead on a wide forest path. At the end, turn left at an acute angle and follow a street. At^{the first} intersection, with Rue de la Fauconnerie on your right, go straight ahead on a shaded path. At the next intersection (forest barrier, plot no. 9), continue straight ahead.

(9) At the crossroads, take the^second road on the right, Allée Royale.

Red and yellow + yellow signposts

At the next crossroads (picnic tables, bike racks), continue straight ahead on Allée Royale. At the end, turn right and go through a forest gate. Continue along a paved road. At the corner of No. 156, turn left towards Boissy RER. Go under a high-voltage power line and cross the median strip of an underground gas pipeline. Then turn right onto the paved road and follow a small car park.

(10) At the entrance to another car park, turn left and enter the Grosbois Regional Forest. Opposite the Maison Forestière des Bruyères, turn right onto Allée Élisabeth towards Boissy RER. Pass through a forest gate and continue straight ahead on the tarmac road.

Red and yellow markings

Take the^first road on the left, which is also paved. At the crossroads, go straight ahead. Then turn right onto the road that becomes Allée du Moulin. Walk along a wall on your left and ignore a road on your right.

(11) Take the next road on the right, Allée du Clocher (a stabilised road). At a crossroads (plot no. 18), go straight ahead. Then cross a wide lane (Allée Élisabeth), cross a stream and take a dirt track that is narrower than the one you were on before. The track narrows and leads to a T-junction.

(12) Turn right and follow a path that winds through the woods (the OSM map is a little confusing here, but the route is easy to follow). At the next T-junction, follow a path not shown on the OSM map (but shown on the IGN map) to the right. Go through a gate and you will come to a paved path. Follow it to the right. After about 40 metres, turn left into a street. Immediately take the^first right, Rue André.

(13) Shortly before the end, just before a bakery, turn left and cross Rue André and then Rue de Sucy at the pedestrian crossings. Then turn right and cross Allée de la Pompadour (incorrectly named by OSM) in two stages, leaving a small sculpture on your right. Then turn left and take a paved path parallel to the street.

Red and yellow + yellow signposts

When the main street turns left, continue straight ahead into a dead-end street and follow the wall of the Château du Piple park on your right. At the castle gate, framed by two brick buildings, turn left onto a path that enters a wood. Pass under the high-voltage power lines and continue on a good path. At the end, follow a road on the right and enter Boissy.

(14) Pass the foot of the Church of Saint-Léger and continue straight ahead on Rue de l'Église (note the beautiful house at No. 6). At the end, turn right onto Rue de Paris. Stay on the right-hand pavement and continue straight ahead downhill. At the traffic lights, cross Avenue du Général Leclerc in two stages, using the pedestrian crossing slightly to the right. Turn left and then immediately right to quickly reach Boissy-Saint-Léger station (E).

To return home:
- RER - Line A, towards Cergy or Poissy via Paris and La Défense.

Train timetables: consult the Transilien website.

In dry weather, good sports shoes are sufficient for this route, which is mostly on paved or stabilised paths and streets. In wet weather, some muddy sections require hiking boots.

Bars, restaurants and shops near the two stations (S) and (E). Mini-market and pharmacy at (8). Bakery on Rue André (13). Public toilets in Morbras Park, marked on the map.

Parc du Morbras opening hours:
- Opening: 8:00 a.m.
- Closing times: 5pm from November to January; 6pm in February; 7pm in March and October; 8pm in April and September; 9pm from May to August.

Additional information:
This hike can be combined with the hike "From Saint-Maur to Suçy-en-Brie via the Marne and Morbras Park". At least three combinations are possible, with total distances of around 16, 19 and 22 km. Start with the other hike and see the three suggested ways of combining the two hikes in the "Practical information" section.

Despite the almost constant presence of signposts, a detailed map is always useful (at least the one accompanying this description). The OSM map background was chosen for the PDF because it is better suited to urban areas than the IGN background. For tracking with the Visorando app, it is recommended to download both backgrounds, OSM and IGN, as the latter is better suited to forest sections.

Hike completed by the author on 12 November 2021.

- Paths in Suçy-en-Brie, between (1) and (2).
- Lac du Grand Val (2).
- Parc du Morbras, between (3) and .
- Green corridor, between (5) and (6). In season, this grassy area is maintained by eco-grazing Bretonne Pie Noire cows.
- Pleasant forest paths between (6) and (8) and between (9) and (13).
- Before (11), the Allée du Moulin runs alongside the wall surrounding the Grosbois trotting training centre. A training track is located on the other side of the wall and, depending on the time of year, you can hear the sulkies passing by (but you can only see the horses' ears and the tops of their heads).
- Saint-Léger Church (16th century) (14).