Mackinac Island Great Turtle Half Marathon
Race Day Weather
Comfortable temps
Mild 55°F temps at gun time mean comfortable early miles without overheating risk. Light winds shouldn't be a major factor for pacing. High humidity (89%) will make it harder to cool down through sweat — increase fluid intake accordingly.
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Race Info
The Mackinac Island Great Turtle Half Marathon takes place each October on Mackinac Island, Michigan, a car-free island in the Straits of Mackinac. The course starts in front of Mission Point Resort, follows the shoreline past Arch Rock, crosses the island's interior on bike trails and roads, and finishes in the park in front of Mission Point Resort. A companion 5.7 Mile run and walk start nearby at the resort's Straits Lodge and share the same finish. Both distances also offer a virtual option. The 2026 edition, held October 24, was the race's 30th running.
