KEYS100 Ultramarathon
Decision scores
Six 0–100 scores telling you, at a glance, who this race is for.
Best for
About the Race
Registration is open for the 18th Annual race across the islands of the Florida Keys--May 16-17, 2026. This chain of unique and inter-connected islands--some inhabited, some not--end in the City of Key West, just 90 miles from Cuba. This is a pavement race, with approximately 75% run on paved bike paths or sidewalks and the balance on the road shoulder facing traffic. The Florida Keys, known locally as "The Conch Republic", is a spectacular and laid-back sub-tropical paradise, surroun...
Course Profile
Course profile data unavailable for this race.
Course features
Accessibility & inclusion
Vibe & community
We don't have vibe tags for this race yet — organizers can claim the listing to add them.
History & past results
Past finisher times and year-over-year participation will appear here once the organizer publishes them.
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Common questions
How hard is the KEYS100 Ultramarathon Ultra?
We don't have a verified elevation profile yet — check the organizer's course map for the climb breakdown.
What should I wear?
Dress for ~10°F warmer than the standing temperature once you start running. Throwaway long-sleeve at the start, gloves and a hat for sub-50°F mornings, singlet plus visor when it climbs above 60°F. The race-day forecast above is the source of truth closer to the date.
When does it sell out?
No published deadline. Most races raise the entry fee in tiers and can sell out without warning — sign up early if you're committed.
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