Grassy Flats sits at mile marker 59, right around the midpoint of the hundred and twenty miles of islands that make up the keys. A day pass gets you the outdoor fitness area at Harmony Point, the wood fired sauna, the cold plunges, and whatever is sitting on the beach that day. You book it by the hour or by the day, you show up and you use it.
TRAIN
Outdoor fitness area
HEAT
Wood-fired sauna
PLUNGE
Three cold tubs
PADDLE
Boards and kayaks
THE DAY PASS
What is Included in a Day Pass at Grassy Flats?
A day pass covers four things.
01
Outdoor fitness
The outdoor fitness area at Harmony Point. An open air space built around bodyweight and free weight movement.
02
Wood-fired sauna
The Sauna. Wood fired, seats twelve.
03
Cold plunges
The cold plunges. Three tubs, four people each, running at different temperatures so you can work your way down.
04
Watersports
Watersports. Paddleboards and fishing kayaks, out on the beach.
If you book your day pass, you have access to the grounds, showers, and the bar while you are here. Harmony Point (Sauna and Cold Plunge) runs on the hour, so that piece gets booked ahead rather than walked up.
ACCESS OPTIONS · REVIEW-ONLY FIGURES
Pricing and access
Harmony Point runs in one hour sessions and caps at twelve people, which is why it gets reserved rather than walked up. The day pass adds the grounds and the watersports on top of that hour.
If you live down here, the beach club membership is the cheaper way to do this more than a handful of times a year
TRAIN OUTSIDE
The Outdoor Fitness Area at Harmony Point
Harmony Point is the far west end of the property, past the lagoon, where the land runs into the water.
Where did the name Harmony Point come from?
The name came from John Denny. Big wave surfer out of Maui, the guy who brought the first paddleboards down to this stretch of the Keys, and he used to go out to that corner to meditate because it was the quietest spot on the property. It still is. The landscaping out there is dense, the deck sits under shade cloth, and the palms do most of the work of keeping the sun off you.
Can I work out at Grassy Flats?
Yes, we have an outdoor fitness area!
What kind of Gym Equipment is at Grassy Flats?
Pull-up bars
Monkey bars
A dip rack
A bench with kettlebells and dumbbells
A rower
A couple of assault bikes
Built to sit outside in the salt air and keep working. No mirrors, no machines, no membership.
What is the Gym at Grassy Flats for?
Moving the way you're going to move on the water. Pulling, hanging, pressing your own bodyweight, getting your heart rate up. That's what's out here, and it's all you will need.
What our Gym isn’t for:
A program. If you're mid-cycle on something specific and you need a squat rack and a loaded barbell, this won't cover it. If this is your goal, let us know and we'll point you to what's nearby.
The pairing that works: twenty minutes out here, then the sauna. You don't need an hour of lifting to earn the heat.
Pull ups, dips, carries, bike intervals, rowing. Movement under load instead of load in isolation.
Why Are There No Machines at Harmony Point?
A machine puts you on a fixed path through one plane, which is useful if you want a specific muscle to grow and less useful if you want to hold an edge in chop for an hour. The equipment out there asks your whole body to participate.
It is also why it is outside. Heat, humidity, uneven footing, sun. Training in the conditions you are about to go perform in is not a small advantage, and the Keys supply the conditions for free.
RECOVERY & CIRCUIT
Sauna & Cold Plunge
The sauna is wood fired and seats twelve. Two benches, cedar, the heat coming off a real fire rather than an element in a box.
The plunges are three tubs, four people each, built by John Kleener at Live Water Sports. John is an old kiteboarding guy who had a paddleboard factory and realized the same roto molding process makes a very good cold tub, so now he makes those too. His shop is close enough that when something needs attention he comes over.
Are the Cold Plunges Kept Clean?
Water quality is the part worth slowing down on. The plunges run a multi stage chemical free filtration system on hydrogen peroxide, and it clears Department of Health standards for shared water with room to spare.
What is the Protocol?
01
Heat
Twelve minutes in the sauna.
02
Cold
Three minutes in the plunge.
03
Repeat
Three rounds.
Dry heat runs 170 to 190 degrees, which is the range for the cardiovascular benefit. If you want steam, the room runs cooler, around 120 to 140, and aromatherapy is available. Both are good. They are doing different things to you.
The three tubs sit at roughly 55, 50, and low 40s, so you can start manageable and work down as you go.
One thing about the three minutes. Alone, most people get out at ninety seconds. With four other people in the tub counting it down, almost nobody does. Matt has watched that play out enough times to build the group sessions around it, and the sauna ends up being where people actually talk to each other.
ON THE WATER
Watersports included with your pass
You can find paddleboards and fishing kayaks on the beach.
Paddleboards
The boards are Live catamaran style, which means two hulls and a lot of stability. Wide enough to do yoga on and steady enough that people take a cooler out. Dogs ride them constantly.
Fishing kayaks
The kayaks are OldTown, set up for fishing with rod holders and room for a tacklebox. There are guests who are on the water at six in the morning, thermos in hand, and do not come back until the afternoon.
Where are you Kayaking and Paddleboarding in the Keys?
At Grassy Flats we have water that is shallow, clear, protected, and when the wind goes down, the water is glassy enough to see the bottom the whole way out.
If you want to push past paddling, the cable park and the kiteboarding lessons are the next step. And they run out of the same stretch of water. Those book separately.
BOOK SEPARATELY
Add-Ons and Upgrades
Everything listed above is what comes with the pass. These additional offerings, book on their own.
Kiteboarding
Kiteboarding. The progression starts on the cable, which is the cheapest way to learn board control, then moves to an intro session, then to open water with an instructor. Full breakdown on the lessons page.
Guided paddles
Guided paddles. Sunrise outrigger goes out as a six seat canoe, one seat at a time, and it is the most underrated thing on the property. Sandbar sails run in the afternoon.
Cable park and Aqua Park
The cable park and the aqua park. The cable runs a tow system you can ride for a session or a day. The aqua park is the inflatable course out on the lagoon, which is mostly families and mostly chaos, in a good way.
Fishing and backcountry
Fishing and backcountry. Half days and full days with a captain, out into the backcountry where the flats open up. The fish calendar page covers what is running and when.
The Front desk can stack any of these onto a day pass when you book.
FIND YOUR FIT
Who This is For?
Overseas Highway travelers
If you are driving the Overseas Highway. Six hours in a car, a cooler in the back, and the plan is Key West tonight. Stopping here breaks the drive in a way that a gas station and a slice of key lime pie does not. Train, sauna, plunge, shower, get back in the car feeling human. People do this on the way down and on the way back up.
Locals
If you live here. Marathon, Grassy Key, Islamorada, Big Pine. The membership is built for you and it is the cheaper way to do this more than a handful of times a year. Details down in the membership section.
Guests staying elsewhere
If you are staying somewhere else in the Keys. Most properties down here have a treadmill, two dumbbells, and a room with no windows. If you have a week booked up or down the road and you want one real training day, or you want a sauna and a plunge you can trust, this is a twenty minute drive from a lot of places and a reasonable one from most of the rest.
Water people
If you are here for the water. Riders waiting on wind, paddlers between sessions, anyone who got worked yesterday and needs to be good for tomorrow. The plunges exist mostly because of you.
HONEST FIT
Who Should Book Somewhere Else
If what you want is a climate controlled room with a squat rack, a mirror, and a full line of machines, there are real gyms in Marathon that do exactly that and do it well.
Is there a Spa at Grassy Flats?
There is no masseuse on staff. We work with practitioners nearby and can bring someone in with advanced notice. So ask when you book rather than when you arrive.
And if the plan is a lounge chair, a drink, and six hours of not moving, there are properties in Marathon built entirely around that and they are good at it. This place is set up for people who came to do something.
BEFORE YOU ARRIVE
Rules and What to Bring
· Book ahead. Harmony Point runs in one hour sessions and caps at twelve people. Walk ups get turned away on busy days.
· Check in at the front desk. That is how towels and setup are ready when you get out there.
· Shower between the sauna and the plunge. Every round. This one is not flexible and the reason is in the section above.
· There is a waiver. Sign it when you book so you don’t have to deal with it later.
· Bring a water bottle. No outside food or drink. There are filtration stations around the property and the bar is open, so you can refill anywhere. You can also grab something from the Market.
· Bring a swimsuit and whatever you train in. Towels are provided. Outdoor showers are there when you are done.
· Do not come under the influence. Heat and cold both put real load on your heart and alcohol or anything else stacked on top of that is how people get hurt.
· If you are pregnant, have a heart condition, or are on medication that affects how you handle heat or cold, talk to a doctor before you book. Hot and cold exposure is not neutral and twelve minutes at 190 degrees is a genuine cardiovascular event.
RESERVE YOUR VISIT
How To Book
Pick your hour, pick your day, book it. A day or two of lead time is usually enough and the same day is a gamble.
The Front desk can stack a lesson, a charter, or a cable session onto the same booking. Easier to sort out when you reserve than when you show up.
FAQ