La Guyancourse

About the Event

Celebrate a major milestone on Sunday, April 12, 2026, as the Guyancourse hosts its special 30th-anniversary edition. Organized by the Entente Athlétisme Saint Quentin en Yvelines (EASQY), this landmark event takes place in the scenic surroundings of Guyancourt, leading participants through the beautiful Minière ponds and the lush forests of Satory. Whether you are a competitive trail runner, a Nordic walker, or a family looking for a healthy outing, the Guyancourse offers a diverse range of slightly hilly, nature-focused routes. As part of the anniversary celebrations, all adult participants will receive an official technical T-shirt, and every child finisher will be honored with a commemorative medal.

30th Edition Race Categories and 2026 Program

Race Type	Distance	Key Highlights	Target Audience
Trail Experience	22 km	UTMB Index; Satory Woods & Versailles views.	Experienced Runners
Nature Run	11 km	Forest trails and lakeside paths.	All Levels
Nordic Walk	14 km	Technically accessible walking route.	Walkers
Para-Athletics	2 km	Inclusive adult race.	Athletes with disabilities
Children’s Races	Various	4 courses; 1 dedicated to adapted sport.	Kids & Juniors

The Guyancourse 2026 is committed to being an inclusive, eco-responsible, and community-driven event. From the 22km trail—featuring an official UTMB index that circles the historic Pièce d'Eau des Suisses in Versailles—to the various children's races, the organizers at EASQY emphasize the spirit of sharing and personal achievement. Participants are encouraged to register early to take advantage of the anniversary surprises and secure their official 30th-edition gear. With full professional timing, dedicated volunteer support, and a festive race village, the Guyancourse remains a premier destination for trail running in the Yvelines region. Join us for this unique sporting adventure on April 12th!

Races Offered

22 km

Apr 12, 2026

straighten

Distance — 22K

terrain

Type — Running

timer

09:15

sell

€27.00

Nordic walk

Apr 12, 2026

straighten

Distance — 14K

terrain

Type — Running

timer

09:30

sell

€20.00

11 km

Apr 12, 2026

straighten

Distance — 11K

terrain

Type — Running

timer

10:00

sell

€20.00

Weather Overview

These values represent the 3-year monthly averages for April in Trappes.

Temp (°C)

Feels Like (°C)

thermostat 6.0° / 15.3°

wb_sunny 2.7° / 12.0°

Wind (km/h)

Humidity (%)

air 12.7 /

water_drop 77.3%

Temp (°C)

Feels Like (°C)

Wind (km/h)

Humidity (%)

thermostat 6.0° / 15.3°

wb_sunny 2.7° / 12.0°

air 12.7 km/h

water_drop 77.3%

About Trappes

Learn more about the host city, Trappes.

Trappes is a commune in the Yvelines department, Île-de-France region, Northern France. It is a banlieue located in the western outer suburbs of Paris, 26.7 km (16.6 mi) from the centre of Paris, part of the new town of Saint-Quentin-en-Yvelines.