6400 Main St, Caseville MI
Saturday, April 25th, 2026
Thumb Coast Ultra & Relay is a one-of-a-kind spring ultramarathon in Michigan’s Thumb. On Saturday, April 25, 2026, runners and ruckers will take on the challenge of racing from Lake Huron in Harbor Beach to Saginaw Bay in Caseville in the 50 Mile division—or team up with friends for the 50 Mile Relay. The 50K features a flat out-and-back course starting and finishing in Caseville.
This race offers the rare opportunity to run point-to-point across the Thumb on mostly dirt and unimproved rural roads. With just 500 feet of elevation gain in the 50 Mile and 300 feet in the 50K, it’s a course that is both approachable for first-time ultrarunners and fast enough for seasoned athletes looking to chase a personal best. Generous cutoff times allow all participants a chance to achieve their goal, while 50 Mile finishers who “beat the sun” with a daylight finish earn a unique prize in addition to their medal.
Thumb Coast Ultra & Relay is more than just a race—it’s a test of endurance, teamwork, and determination supported by a welcoming community. Participants can expect a well-marked course, fully stocked aid stations, and the camaraderie of runners, ruckers, and relay crews tackling the same adventure together.
Date: April 25, 2026
Location: 6400 Main St, Caseville, MI
More Info: Visit the official race page at Thumb Coast Ultra & Relay.
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