Tackle the legendary slopes of the Vosges Mountains at Les Courses du Grand Ballon on Sunday, May 10, 2026. This classic mountain running festival, organized by the Union Sportive Thann Athlétisme, offers three epic challenges all starting from the village of Willer-sur-Thur, each culminating at or near the summit of the Grand Ballon, the highest peak in the Vosges. Choose the pure ascent of "La Montée" (14.2 km, 1220m D+), a demanding mountain race that is part of the prestigious Trophée des Vosges, the scenic loop of "Le Défi" (25 km, 1320m D+), a true trail adventure, or the accessible "Mini-Trail de l'Ostein" (9 km, 350m D+), a perfect introduction to trail running with stunning valley views. The event is renowned for its fantastic organization, including free shuttle buses that solve the classic point-to-point logistics, allowing runners to descend comfortably from the summit after their monumental effort. With its mix of serious competition in "La Montée" and inclusive trail options, it attracts a wide range of athletes, all united by the challenge of conquering this iconic peak. The finish line on the high alpine pastures, with panoramic views stretching across the Rhine valley, provides an unforgettable reward and a profound sense of achievement. For any mountain runner or trail enthusiast, this event is a must-do pilgrimage to the roof of the Vosges.
Races Offered
Trail 25 km
May 10, 2026
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Distance —
25K
terrain
Type —
Others
timer
08:30
14.2 km
May 10, 2026
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Distance —
14.2K
terrain
Type —
Others
timer
10:00
Trail 9 km
May 10, 2026
straighten
Distance —
9K
terrain
Type —
Others
timer
-152 days remaining
Weather History
These values represent the 3-year monthly averages for May in Willer-sur-Thur.
thermostatTemperature
9.9° / 18.7°
wb_sunnyFeels like
7.8° / 16.5°
light_mode
Avg sunshine hours
10h 51m
water_drop
Avg rainfall
3.2 mm
ac_unit
Avg snowfall
—
air
Avg wind speed
8.8 km/h (Light breeze)
opacity
Sweat loss rate
Low
terrain
Course conditions
Firm and slightly soft
sunny
Max UV Index
Moderate (4.2)
humidity_mid
Humidity
70.8%
wb_twilight
Sunrise
05:52
nightlight
Sunset
21:02
About Willer-sur-Thur
Learn more about the host city, Willer-sur-Thur.
Willer-sur-Thur is a commune in the Haut-Rhin department in Grand Est in north-eastern France.
