GR1: Stage 4 - Vernouillet-Verneuil to Cergy-le-Haut (21 km)

Hello everyone!
GR1 Tour de Île-de-France – Stage 4
Let’s continue our trek around Paris with another stage of the GR1, this time in the west of Parisian area, in the Parc naturel régional du Vexin français. During this stage, we will cross administrative regions, moving from Yvelines to Val-d’Oise. We’ll explore a varied landscape of forests, open fields, and small villages — a great opportunity to discover the far west of Île-de-France.
To keep the day manageable (around 20 km), near the village of Sagy we will leave the GR1 trail and head toward Cergy-le-Haut RER A station. This section lies at the very edge of Île-de-France, takes longer to reach, but is especially interesting to explore.
‼️ Around the village of Évecquemont, a 1.5–2 km detour may be required due to closed paths.
The GR1 Project is an opportunity to explore the natural beauty of the Île-de-France region, all within easy reach of Paris. Spanning a total of 550 km, this circular trail goes around the city in a clockwise direction, offering a unique way to discover peaceful landscapes, charming forests, and picturesque villages surrounding Paris.
🗺️ Our trail: https://mapy.com/s/mokukuvufe

📍 Meeting Point
Sunday, Jan 18, at 09:45 AM
Vernouillet–Verneuil train station – in front of the station.
To get there, take train line J from Gare Saint-Lazare at 09:15, arriving at Vernouillet–Verneuil at 09:45.
(Please try to catch this train — otherwise you will arrive too late.)
‼️ I know it’s early, but we have a long day and we’re going far!

🎯 Ending Point
We will finish at Cergy-le-Haut RER A station. From there, RER A trains reach Paris in 30–40 minutes.
(The exact timetable is not yet available.)

🥪 Lunch
We’ll stop for lunch/snacks in the forest, so please bring your own food and water.

📏 Hike Details

• Distance: ~21 km
• Elevation gain: +380 m
• Duration: ~6 h (including breaks and lunch)
• Difficulty: Moderate – you should be comfortable walking 10–15 km in your day-to-day routine.
• Language: English – ideal for expats and anglophones living in or visiting Paris.

You are responsible for your own actions — please make sure you feel comfortable with the distance and act responsibly.

🎒 What to Bring

• Small backpack
• 1L of water
• Lunch/snacks
• Comfortable walking shoes
• Rain jacket or umbrella

⭐ Participation
€10 per person, cash or via Revolut/Lydia, payable at the end of the hike.
(If you don’t have a Navigo Pass, a round-trip train/metro ticket is about €5.)
See you there!
Mihai