40/50 Mile Challenge - Cliff Cave
Oakville, United States • 22 Aug 2026
40/50 Mile Challenge - Cliff Cave
The 40/50 Mile Challenge is a continuous loop trail race held at Cliff Cave Park, using a clearly marked 3.1 mile (5K) loop on the River Bluff Trail. The course runs through wooded hillsides and limestone bluffs and includes overlooks of the Mississippi River.
Trail surface is mainly packed dirt with sections of crushed limestone and natural singletrack. The route contains roots, short climbs, rolling hills, and a few technical areas on bluff-side sections. Runners return to the same central start and finish area each lap where a fully stocked aid station is available.
Runners may access personal supplies from a designated staging area each loop. Crew access is permitted in designated areas and pacers are allowed subject to location specific and time based rules. Medical and race staff are on site throughout the event. The event runs simultaneously with The Next Loop Endurance Series on the same course; Next Loop participants run on the hour while 40/50 Mile Challenge competitors run continuously and are scored separately.
Event format details include a 12 hour time limit and continuous loop racing on a 3.1 mile trail. Location is Cliff Cave Park, 806 Cliff Cave Rd, St Louis, MO, 63129.
Distances Offered: Visit the organization's website for the most recent information.
- 40 Mile
- 50 Mile