River of No Return Endurance Runs

You are not at the top of the food chain here. Better run fast. The River of No Return Endurance Runs return to Challis, Idaho, on Saturday, June 20, 2026. Choose 108k (17,600 ft gain, 22 hours), 55k (8,800 ft gain, 12.5 hours), or 32k (4,500 ft gain). Start and finish at Challis City Park (except 32k starts at the ghost town of Bayhorse — shuttle provided). Wolf, coyote, fox, bear, cougar, elk, deer, eagles. Forgotten mines and old Idaho traditions. Crew‑friendly aid stations accessible without 4WD. Finish with a final mile down Main Street Challis as locals cheer you home.

Location & Terrain:

• Challis, Idaho — gateway to the Frank Church River of No Return Wilderness, the largest contiguous wilderness area in the lower 48 states
• Start/Finish: Challis City Park (right next to the high school)
• 32k start: Bayhorse Ghost Town — an abandoned mining settlement with historic structures
• Courses traverse ATV‑width two‑track trails, dirt roads, single‑track elk trails, and 5 miles of pavement at the finish (108k)
• Big mountain climbs: cresting 8,000', 9,000', and 10,000' (108k)
• First 9 miles of all races share the same route — spectators can watch the start, then drive to aid stations

Wildlife & Atmosphere:

• Elk, deer, eagles, bears, wolves, cougars, coyotes, foxes — you are not at the top of the food chain
• Forgotten mines and mining communities dot the landscape
• Old Idaho traditions and the very supportive community of Challis
• Finish line: fast final mile down Main Street Challis — crew and fans can run alongside you to the park

Support Crews (Highly Encouraged):

• 108k crews can support at Bayhorse (16M), Bayhorse Lake (36.5M), Squaw Creek TH (45.6M), and Custer Motorway (61.7M). Crews may also run down Main Street with runners.
• 108k runners may pick up a pacer after mile 36.5 (Bayhorse Lake).
• 55k crews can support at Bayhorse (16M) and run down Main Street with their runner. No pacing elsewhere.
• 32k has no crews — "force your crew to register and run the 32k with you!"
• Aid stations are crew‑accessible without 4WD — gorgeous drives along the Salmon River.

Aid Stations & Cutoffs:

• 108k: 9 aid stations, intermediate cutoffs (see race website for specific times).
• 55k: 5 aid stations, 12.5 hour total cutoff.
• 32k: 2 aid stations.
• Fully stocked, top‑notch aid stations (water, electrolyte, food, etc.)

What's Included:

• Chip timing
• Finisher medal
• Event shirt (included with registration)
• Post‑race food and refreshments at Challis City Park
• Medical support on course
• Shuttle to 32k start (from City Park)

Registration & Refunds:

• Registration closes Monday, June 1, 2026 at 11:59 PM MT
• Full refund less $20 given up to May 1
• 50% refund after May 1
• No refunds after June 1

Idaho Trail Ultra Series:

• This race is part of the Idaho Trail Ultra Series — www.idahotrailultraseries.com
• Earn series points and compete across multiple Idaho ultras

Past Performances (108k Men):

• Canyon Woodward — 10:58:42 (2025) — course record
• Jimmy Elam — 11:03:34 (2021)
• Cody Lind — 11:11:20 (2024)

Organizer: Pulse Running.