This event is in the past.It took place on August 15, 2026 at Underdown Recreation Area.
💧Bring your own water for camping
🦟Bring plenty of mosquito repellent
🔋Bring a generator for rustic camping
Thunderdown in the Underdown is a grassroots mountain bike race in Northern Wisconsin. Racers tackle a challenging wilderness course featuring singletrack trails, glacial terrain, and dozens of boardwalks.
grassroots trail racing
mountain bike challenge
wilderness trail running
challenging singletrack
💧Bring your own water for camping
🦟Bring plenty of mosquito repellent
🔋Bring a generator for rustic camping
Thunderdown in the Underdown is a grassroots mountain bike race in Northern Wisconsin. Racers tackle a challenging wilderness course featuring singletrack trails, glacial terrain, and dozens of boardwalks.
grassroots trail racing
mountain bike challenge
wilderness trail running
challenging singletrack