Florida · 100 Miler · 50 Miler · 50K
KEYS100 Ultramarathon
KEYS100 Ultramarathon is a 100 Miler, 50 Miler and 50K event held in Key West, Florida. Its next confirmed date is Saturday, May 15, 2027. About 7,448 runners take part across all distances.
- Race day
- May 15, 2027
- Location
- Key West, FL
- Field size
- ~7,448 runners
Race details
- Date
- Saturday, May 15, 2027
- Location
- Key West, Florida
- Distances
- 100 Miler, 50 Miler, 50K
- Field size
- About 7,448 runners
- Course
- Flat, entirely paved course along the Overseas Highway near sea level; the only rises are over causeway bridges such as the Seven Mile Bridge.
- Registration
- runsignup.com
- Official website
- keys100.com
Registration, course & weather
- Registration status
- Open
- Entry fee
- Listed fee for the longest distance, $305 (from runsignup.com, checked September 25, 2026)
- Start time
- 5:30 AM EDT
- Course profile — 100 Miler
- Point-to-point course; Road surface
- Course profile — 50 Miler
- Point-to-point course; Road surface
- Course profile — 50K
- Point-to-point course; Road surface
About the KEYS100 Ultramarathon
Registration is open for the 19th Annual race across the islands of the Florida Keys--May 15-16, 2027. 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 and sidewalks, parallel pedestrian bridges and portions of the old service road. The balance is run on the road shoulder facing traffic--and close to it. (Awareness and caution are paramount whe…
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KEYS100 Ultramarathon: common questions
- When is the KEYS100 Ultramarathon?
- The next confirmed date is Saturday, May 15, 2027.
- Where is the KEYS100 Ultramarathon held?
- In Key West, Florida.
- What distances does the KEYS100 Ultramarathon offer?
- 100 Miler, 50 Miler and 50K.
- How many people run the KEYS100 Ultramarathon?
- About 7,448 runners across all of its distances. That figure is an estimate of the field size, not an entry cap.
- How do I register for the KEYS100 Ultramarathon?
- Registration is handled by the organiser at runsignup.com. Entry fees, caps and deadlines are set there.
- Is registration open for the KEYS100 Ultramarathon?
- Yes — registration is open. Listed fee for the longest distance, $305 (from runsignup.com, checked September 25, 2026).
- What time does the KEYS100 Ultramarathon start?
- 5:30 AM EDT.
Plan this race in RaceRove
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