KEYS100 Ultramarathon
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KEYS100 Ultramarathon : Overview
KEYS100 is a point-to-point ultramarathon across the islands of the Florida Keys, held May 16-17, 2026. Races start on the mainland and finish at Higgs Beach in Key West. The course is on pavement: about 75% on paved bike paths or sidewalks and the remainder on the road shoulder facing traffic. The event includes multiple race options for individuals and teams.
Distances
- 100 miles individual and team relay
- 50 miles individual and team relay
- 50 kilometers individual
Race format, support and rules
Individual runners must have a registered support crew or share one under strict meet-up rules. Relay teams may include up to six runners for the 100-mile event and up to three for the 50-mile event. Each team or individual is limited to one support vehicle; vehicle types, size and marking requirements are specified and subject to inspection. Safety gear is required - participants and crew receive high-visibility reflective wear at check-in and must use additional lighting and reflective gear during nighttime hours. Pacers are allowed at specified locations for each distance. Timing equipment and interim timing stations are used; each distance has an overall time limit and interim cutoffs. Rules prohibit IVs, supplemental oxygen, drones, unregistered supporters on course, and pacing by non-registered personnel. Violations can result in penalties or disqualification. Visit the organization's website for the most recent information.
