River Of No Return Endurance Runs

River of No Return Endurance Runs : Challis, ID

The River of No Return Endurance Runs are trail ultramarathons with a start and finish at Challis City Park for two distances and a Bayhorse start for the shorter distance. Courses pass through mountain terrain, old mining areas, and river corridors with regular wildlife sightings such as elk, deer, eagles, bears, and wolves. Runners experience multiple high-elevation climbs, including crests above 8,000, 9,000, and 10,000 feet.

Distances offered:

• 108K
• 55K
• 32K

Course specifics: the 108K is a large single-loop route with about 17,600 feet of elevation gain, nine aid stations, mostly two-track trail with sections of single track, dirt road, and several miles of pavement approaching Challis. The 55K has about 8,800 feet of gain, five aid stations, narrow ATV trails, single-track elk trails, and a lollipop-type loop that partially follows the 32K route. The 32K is a point-to-point return to Challis with about 4,500 feet of gain and two aid stations; shuttles are provided to its start at Bayhorse.

Support and logistics: the courses are crew-friendly with multiple aid stations accessible to support teams without four-wheel-drive vehicles. Runners may be accompanied by crews and fans for the final mile down Main Street into Challis City Park. Refund policy: full refunds minus $20 until May 1, 50% refund after May 1, and no refunds after June 1. The event is part of the Idaho Trail Ultra Series. Visit the organization's website for the most recent information.