Trail running course near Whitewater, Wisconsin, USA
tBunk Endurance Challenge

tBunk Endurance Challenge

50 miles·295 ft gain·Whitewater, Wisconsin
ultranighttrailloop50 mile

AI-generated image

Distance50 miles
Gain295 ft
DateAnnual · Nov

Registration is closed for tBunk Endurance Challenge

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About This Race

The 50-mile distance serves as the gateway option for runners looking to test themselves against Bunk's demanding terrain without committing to the full century challenge. This distance allows you to experience the complete character of the course while maintaining a more manageable pacing strategy, making it ideal for those stepping up from shorter ultras or seeking a solid training benchmark. Runners will face the same technical challenges as the 100-mile field but with less pressure on overnight fueling and sleep deprivation management.

Elevation Profile

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

The course gains 295 ft over 50 miles, with the steepest section between mile 65–mile 65.

Location

Other Distances at This Event

100 miles

2,671 ft gain

The race unfolds entirely on the Nordic Blue loop, a 9.19-mile circuit that delivers 1,700 feet of elevation gain per lap. This creates a rolling challenge that accumulates significant vertical gain over the full distance while maintaining a predictable rhythm for pacing and nutrition planning. Runners will encounter an unmanned aid station at the halfway point of each loop, with the fully-stocked main aid station positioned at the start/finish area. The consistent loop format allows for strategic planning and crew support while the maintained trail surfaces ensure reliable footing regardless of weather conditions.