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

Dirty Burg — 50K

50K·2,070 ft gain·Belmont, Michigan
ultra50kforesttrailloop

Photo by Kameron Simpson on Unsplash

Distance50K
Gain2,070 ft
DateAnnual · Jul
Difficulty3/5

Registration is closed for Dirty Burg — 50K

Get alerted if spots open up or when next year's registration goes live.

About This Race

The 50K distance represents the full Dirty Burg experience, weaving through extended sections of the area's trail system. This ultra-distance option demands sustained effort and smart pacing across varied terrain. Runners seeking their first ultramarathon or veterans looking for a well-supported long-distance challenge will find the course both demanding and rewarding.

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 2,070 ft over 31 miles, with the steepest section between mile 12–mile 12.

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.

25K

351 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.