Trail running course through mixed terrain in Michigan, USA
Dirty Burg

Dirty Burg — 25K

25K·351 ft gain·Belmont, Michigan
foresttrailloop

Photo by Kameron Simpson on Unsplash

Distance25K
Gain351 ft
DateAnnual · Jul
Difficulty2/5

Registration is closed for Dirty Burg — 25K

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About This Race

The 25K strikes a balance between substantial distance and manageable commitment, making it a natural stepping stone for runners advancing their trail running goals. This middle-distance option covers significant ground while remaining accessible to those building toward longer efforts. The course provides enough challenge to test fitness without the extended time commitment of ultramarathon distances.

The race is built around a 10K loop that combines approximately 5.5 miles of rolling single track with a challenging 0.7-mile ski hill segment. The 5K uses the same loop with a shortcut, positioning the ski hill climb at the end of the race. Distance runners face the ski hill multiple times: 25K participants complete one 5K loop followed by two 10K loops, while 50K runners take on the full 10K loop five times.

The single track sections wind through the natural terrain around Cannonsburg Ski Area, offering typical Michigan trail conditions with rolling hills and forest paths. The ski hill segment provides the course's most significant elevation challenge, requiring runners to ascend and descend the slope that serves skiers in winter months.

Elevation Profile

Elevation profile estimated from terrain data. Actual course may differ.

The course gains 351 ft over 16 miles, with the steepest section between mile 19–mile 19.

Location

Notable Features

The race's signature element is the ski hill climb and descent, which becomes increasingly challenging as ultra runners face it multiple times. The loop-based format creates excellent opportunities for spectating and crew support while the combination of rolling single track and ski slope terrain offers a distinctive running experience not commonly found in Midwest trail racing.

Other Distances at This Event

5K

The race is built around a 10K loop that combines approximately 5.5 miles of rolling single track with a challenging 0.7-mile ski hill segment. The 5K uses the same loop with a shortcut, positioning the ski hill climb at the end of the race. Distance runners face the ski hill multiple times: 25K participants complete one 5K loop followed by two 10K loops, while 50K runners take on the full 10K loop five times. The single track sections wind through the natural terrain around Cannonsburg Ski Area, offering typical Michigan trail conditions with rolling hills and forest paths. The ski hill segment provides the course's most significant elevation challenge, requiring runners to ascend and descend the slope that serves skiers in winter months.

10K

157 ft gain

The race is built around a 10K loop that combines approximately 5.5 miles of rolling single track with a challenging 0.7-mile ski hill segment. The 5K uses the same loop with a shortcut, positioning the ski hill climb at the end of the race. Distance runners face the ski hill multiple times: 25K participants complete one 5K loop followed by two 10K loops, while 50K runners take on the full 10K loop five times. The single track sections wind through the natural terrain around Cannonsburg Ski Area, offering typical Michigan trail conditions with rolling hills and forest paths. The ski hill segment provides the course's most significant elevation challenge, requiring runners to ascend and descend the slope that serves skiers in winter months.

50K

2,070 ft gain

The race is built around a 10K loop that combines approximately 5.5 miles of rolling single track with a challenging 0.7-mile ski hill segment. The 5K uses the same loop with a shortcut, positioning the ski hill climb at the end of the race. Distance runners face the ski hill multiple times: 25K participants complete one 5K loop followed by two 10K loops, while 50K runners take on the full 10K loop five times. The single track sections wind through the natural terrain around Cannonsburg Ski Area, offering typical Michigan trail conditions with rolling hills and forest paths. The ski hill segment provides the course's most significant elevation challenge, requiring runners to ascend and descend the slope that serves skiers in winter months.