KEYS100 Ultramarathon

MAY
16-17
2026
Read all about the KEYS100 Ultramarathon on 16-17 May 2026 in Key West.
16-17 May 2026
100 miles 50 miles 50 kilometers

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About the race

KEYS100 Ultramarathon is a 100-mile, point-to-point race across the Florida Keys, from Key Largo to Key West. It also offers a 50-mile option (Marathon to Key West) for individuals and teams, and a 50-kilometer race from Big Pine Key to Key West. All events finish at Higgs Beach on the Atlantic in Key West.

The course unfolds along a tropical island chain, with a festive finish zone under a large tent offering cooked food, drinks, and awards. Runners compete as individuals or in up-to-six-person relay teams; support crews leap-frog along approved meet-up locations since there are no formal aid stations. Marshals, medical staff, and law enforcement ensure safety; timing is provided by MCM Timing. Visit the organization's website for the most recent information.

100 mi
100-Mile Race From Key Largo to Key West
50 mi
50-Mile Race From Marathon to Key West
50 km
50-Kilometer Race From Big Pine Key to Key West

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