The Nature's Challenge Race, set for Sunday, October 25, 2026, offers an exhilarating experience with a self-paced three-hour duration over a four-kilometer trail. This second edition is limited to just 200 participants and can be run solo or as teams of two. Each runner has complete freedom in their timing; they may start, stop, and even pause whenever desired—though wearing the race number is mandatory during your run. The event kicks off at 9:00 AM with a cut-off time for completion by 11:45 AM to ensure safety on the challenging terrain. Entry fees are €10 per individual or €15 per duo, and all proceeds will support the Eugène Marquis Center. The race is open only to those holding an official permit or license. For those who prefer a more leisurely pace, a free walking option with donations benefiting the same center is available, starting at 10:00 AM. Registrations are now open from June 14, 2026, at noon; mark your calendars and prepare to embrace this unique outdoor challenge. The picturesque route will take you through diverse landscapes, ensuring a memorable experience for all participants. Whether you're aiming for personal bests or simply enjoying the natural beauty around you, there’s something here that suits every runner's spirit.
Races Offered
Defi Nature de Clayes par équipe
Oct 25, 2026
straighten
Distance —
4 km
terrain
Type —
Running
timer
114 days remaining
sell
€16.20
Défi Nature de Clayes
Oct 25, 2026
straighten
Distance —
4 km
terrain
Type —
Running
timer
114 days remaining
sell
€11.00
Marche Nature
Oct 25, 2026
straighten
Distance —
8 km
terrain
Type —
Running
timer
114 days remaining
sell
€2.00
Weather History
These values represent the 3-year monthly averages for October in Clayes.
thermostatTemperature
9.9° / 17.5°
wb_sunnyFeels like
7.5° / 15.1°
light_mode
Avg sunshine hours
7h 3m
water_drop
Avg rainfall
2.9 mm
ac_unit
Avg snowfall
—
air
Avg wind speed
13.0 km/h (Gentle breeze)
opacity
Sweat loss rate
Low
terrain
Course conditions
Firm and slightly soft
sunny
Max UV Index
Low (2.8)
humidity_mid
Humidity
83.2%
wb_twilight
Sunrise
08:28
nightlight
Sunset
19:16
About Clayes
Learn more about the host city, Clayes.
Clayes is a commune in the Ille-et-Vilaine department in Brittany in northwestern France.
