⏵ Course guide · Florida Keys point-to-point
KEYS100 runs 100 miles point-to-point from Key Largo to Key West down the Florida Keys, entirely paved road, entirely self-supported: no aid stations, no water stops, just you and a dedicated crew leap-frogging ahead in the heat. I will walk you through the crew logistics and terrain first, then give you a pacing and fueling plan built for a long, hot, flat day, plus free tools to dial in your own numbers.
These facts come from the official keys100.com race site. Check the current year details, cutoffs, and registration window before you commit. Race logistics change year to year.
KEYS100 is a point-to-point road ultra with a single defining feature: there is no aid on course. Your crew is your aid station, every mile of the way.
The 100-mile race starts at 5:30 AM Saturday at the Key Largo Community Park, with staggered waves of 12 to 15 runners leaving every five minutes to spread the field out along the road. The 50-mile race starts from the Marathon Garden Club, and the 50K starts from the Lower Keys Chamber of Commerce in Big Pine Key, both feeding into the same finish at Higgs Beach in Key West.
This is the single most important thing to understand about KEYS100: there are no aid stations or water stops anywhere on the route. Individual runners and teams are entirely self-sufficient. Your crew leap-frogs you along the course, meeting only at approved locations to hand off water, food, ice, dry clothes, and night gear, and is also responsible for getting you to the start, from the finish, and caring for you if you cannot complete the race.
If running the full distance solo does not appeal, KEYS100 offers relay teams: up to six runners for the 100-mile distance, up to three for the 50-mile. Teams decide their own strategy, how many legs each runner covers, in what order, and how far, with an official list of allowable exchange locations.
With no meaningful elevation change and no crowds of runners around you for long stretches, KEYS100 pacing is a discipline problem more than a terrain problem.
Because your crew has to know roughly when and where to meet you, a realistic finish-time projection matters here more than on a race with continuous aid. Build your goal pace around a flat road ultra effort, not a trail race feel, and share the projected splits with your crew so their leap-frog schedule matches your actual pace rather than a guess.
A mid-May start in the Florida Keys means daytime heat will be a factor for most of your race, and pace that feels sustainable in the cooler early miles often is not sustainable once the sun is fully up. Build a pacing plan that assumes a slower second half rather than banking on even splits across a hot, humid, 100-mile road effort.
⏵ Free tools to pace this course
Every calorie and every ounce of fluid you take in on KEYS100 comes from your own crew, so your fueling plan has to be built around your crew schedule, not around a course that will feed you.
Aim for roughly 60 to 90 grams of carbohydrate per hour, and lean toward the higher end of sodium guidance given the typical heat and humidity of the Florida Keys in May. Since there is no on-course aid to fall back on, agree with your crew ahead of time on exactly what you want at each meet-up rather than improvising mid-race.
With essentially no shade along much of the route, cooling strategy, ice in a bandana or hat, cold towels, and timing your crew stops around the hottest stretches of the day, can matter as much as your carbohydrate plan. Talk through a heat-management plan with your crew before race day, not during it.
⏵ Build your fueling plan
Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and a hot Florida Keys day with the free ultra fueling calculator. Browse the rest of the free running tools at the tools hub.
⏵ Train for it with Summit Line
Get a race-day plan built around YOUR fitness, this exact flat, hot, crew-dependent 100-mile profile, and your projected splits for your crew to plan around. Summit Line reads your real training, builds a plan for a long road effort in the heat, and rehearses your fueling so race day is something you execute, not guess at.
The distance and the flat, paved course make it approachable for road-focused ultrarunners, but the real difficulty is heat, humidity, and logistics. There are no aid stations or water stops anywhere on the 100-mile route down the Keys, so every solo runner needs a dedicated support crew leap-frogging ahead with water, food, ice, and dry clothes. Add typical mid-May Florida Keys heat and you get a race that is as much a crew logistics exercise as it is a running test.
No. KEYS100 runs with zero aid stations or water stops along the entire route. Individual runners and teams are self-sufficient, relying on their own support crew, which leap-frogs the runner along the course, meeting at approved locations only to hand off water, food, ice, and gear. There are stores and places to re-stock along the way, but the race itself provides no on-course support.
With no aid stations on course, your fueling plan lives entirely with your crew. Aim for roughly 60 to 90 grams of carbohydrate per hour, and lean toward the higher end of sodium guidance, 500 to 1,000-plus mg per liter, given the heat and humidity typical of the Florida Keys in mid-May. Because your crew resupplies you at approved meet-up points rather than continuous aid, plan your carry capacity between those checkpoints carefully, especially in the hottest stretches of the day.
Yes, for the individual 100-mile and 50-mile races, a support crew is mandatory. Your crew is responsible for meeting you at approved locations along the course to resupply water, food, ice, and clothing, for getting you to the start and from the finish, and for transporting and caring for you if you cannot finish. Relay teams do not need a separate crew in the same way since teammates handle their own legs, but first-time crews are strongly encouraged to watch the official crewing tutorial before race day.
Up to six runners can form a 100-mile relay team, and up to three runners can form a 50-mile relay team. Teams decide how many legs each runner covers, in what order, and how far, and runners do not have to stay in the same order or run equal distances. A list of allowable exchange locations is provided in the official race guide.
The course runs point-to-point down the Florida Keys along the highway connecting the islands, entirely paved road terrain rather than trail, crossing more than 40 islands between Key Largo and Key West. The environmental challenge, heat, humidity, and sun exposure over pavement with essentially no shade, defines this race more than any technical terrain would.
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<a href="https://runsummitline.com/guides/keys-100">The KEYS100 course guide</a><iframe src="https://runsummitline.com/embed/race/keys-100" style="width:100%;max-width:420px;height:180px;border:0;" loading="lazy" title="KEYS100 course guide by Summit Line"></iframe>This guide is independent and for planning only. The course details, dates, and registration windows come from public sources and can change year to year, so confirm the current specifics with the official race before you register or run. The fueling and pacing advice is general and not medical advice.
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