Thumb Coast Ultra & Relay – 50 Mile, 50K, & 50 Mile Relay – Caseville, MI 2026

Thumb Coast Ultra & Relay – April 25, 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