The walk starts at the RER A station "Le Vésinet le Pecq", on the Avenue Georges Bizet side. There is a car park near the station.
(S/E) When you leave the station, turn right and take Avenue Georges Bizet northwards, against the flow of traffic. Walk to the traffic lights, cross the D311 (Route de Montesson) and take Rue de Seine opposite.
Follow this street to the end, ignoring all the streets on the left. Then go right under the railway bridge and cross immediately to the left at the traffic lights. Follow the small path behind the bus shelter to reach the Seine.
(1) When you reach the Seine, turn left and follow the river along the well-maintained promenade (part of the Paris-London greenway).
(2) Go under the Pont Georges Pompidou (you can take the stairs on the left to find shops if necessary). Continue for about 2.3 km along the Seine.
(3) Just after the water services buildings, you will see a very large gate on your left, which is often closed and marked "Voie privée" (private road). However, the passage is always open to pedestrians via a space on the left: enter and follow this lane to the end (Allée des Machines).
Cross the Chemin de Ronde and then the Allée du Lac Inférieur, continuing straight ahead. When you reach the Lac Inférieur, wade across the large stones (you can also take the bridge on the left).
(4) Cross Avenue du Président Roosevelt and follow Allée de la Gare opposite. Cross Route de Croissy and cross a river.
(5) Then turn left onto Promenade d'Outremont. This promenade is a path that runs alongside one of the small rivers, with several fords that are fairly easy to cross on foot for children aged 4 and above. Continue along the river until you reach an intersection between two avenues.
(6) Turn right and then immediately left onto Avenue Georges Clémenceau. Continue along Avenue de la Prise d'Eau
(7) Follow the path on the right that crosses the Grande Pelouse. Climb the stairs above the railway line to descend on the other side. Continue along the path northwards to cross Boulevard Carnot at the traffic lights and reach the Pelouse des Fêtes. Continue north-northeast across the Pelouse des Fêtes. Join the Piste du Tour du Grand Lac, then turn left to reach the Pont Blanc, which provides access to the Île des Ibis.
(8) Do not cross the bridge, but take the path on the right that runs along the lake. After walking halfway around the lake, you will find a wooden bridge on the left that leads to the island. Cross this bridge and turn right to walk halfway around the island (which is very small), leaving a restaurant on your left. Cross the Pont Blanc again.
(8) At the end of the bridge, turn right immediately and follow the lake. Then leave the lake and head east on Avenue du Grand Veneur. Cross Avenue Marceau and head to Le Vésinet-le Pecq station (S/E).