Florida Keys Atoll · Marquesas Keys

Marquesas Keys — the only natural atoll in the Western Hemisphere.

A ring of uninhabited mangrove islands enclosing a shallow lagoon, 25 miles west of Key West. Frigate birds overhead, sea turtles cruising the seagrass, water clear enough to see baitfish from the bow. The destination you can't reach without a captain.

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Why the Marquesas is unlike any other Keys destination

Three things you only get here.

The Marquesas isn't a sandbar — it's an atoll. The unique geology and 25-mile distance from Key West deliver a destination that doesn't exist anywhere else in the continental U.S.

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The only natural atoll

A ring of islands enclosing a shallow lagoon. There's no other atoll in the Western Hemisphere. Geologists debate exactly how it formed (popular theory: a meteorite). The result is a destination unlike any sandbar in the Keys.

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Sea turtles, frigates, dolphins

Wildlife density is high — the atoll is inside the Key West National Wildlife Refuge. Frigate birds wheel overhead, sea turtles cruise the seagrass beds inside the lagoon, occasional bottlenose dolphins move through the inlets.

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World-class snorkel

The inside of the atoll has shallow patch reefs and seagrass meadows in clear water. Outside the atoll, channel-edge reefs hold larger fish. On calm days the visibility inside the lagoon is among the best in the Florida Keys.

A full-day expedition

What a Marquesas day actually looks like.

From our Perry Hotel & Marina dock, the run to the Marquesas is about two hours westward across open water. Captain Dustin watches the forecast and won't run on rough days. On a calm morning the trip itself is part of the experience — flying fish, frigate birds overhead as you approach the atoll, the ring of mangrove islands rising out of the water on the horizon.

Anchoring inside.

The atoll has several inlets; we anchor inside the protected lagoon. The water is shallow and sandy — you can step off the swim platform into knee-deep clear water. Pick a side based on wind. The inside of the atoll is wind-protected almost regardless of direction.

What you do on site.

Snorkel the inside patch reefs and seagrass beds. Swim to the nearest mangrove edge and explore. Birding — bring binoculars. Some groups bring a paddleboard and circle the inside of the lagoon. Lunch on the boat under the bimini. Most groups spend 3-4 hours inside the atoll before turning home.

Pair with Boca Grande.

Boca Grande Key sits 13 miles east of the Marquesas, on the way back to Key West. Many full-day Marquesas charters add a Boca Grande stop on the return for the empty beach. See our Boca Grande page for details.

The wind condition matters more than usual.

The 25-mile run is across open water with no shelter on the way. South or southwest wind makes the trip rough. Calm conditions make it smooth. Captain Dustin checks forecast 48 hours out and we'll proactively reach out if conditions look unsafe — reschedule is always an option.

How Six Fins gets you to the Marquesas

Two formats, same destination.

Marquesas charters are full-day only. Both options launch from our Perry Hotel & Marina dock on Stock Island. Private-charter only.

Two destinations

Marquesas + Boca Grande

Adds a Boca Grande Key stop on the return. Empty beach plus atoll lagoon in the same day. About 9 hours total. From $2,995.

See Boca Grande →

Marquesas Keys FAQ

The questions guests ask first.

What is an atoll, and why is the Marquesas the only natural one in the Western Hemisphere?
An atoll is a ring of islands or coral surrounding a central lagoon. The Marquesas is the only naturally-formed example in the Western Hemisphere -- most atolls are in the Pacific and Indian Oceans on volcanic foundations. The Marquesas' origin is debated; the popular theory is meteorite impact, though that's not settled.
How long is the trip out?
About two hours each way from Key West, depending on conditions. The 25-mile open-water run means Marquesas is full-day only -- a typical charter is 7-9 hours total.
Can you walk on the islands?
Limited landing -- the islands are inside the Key West National Wildlife Refuge and most have nesting bird closures or are mostly mangrove (not walkable beach). The destination is the lagoon and the snorkeling, not the dry land.
What if the weather is bad?
The 25-mile open-water run is the most weather-sensitive trip we offer. South or southwest wind makes it rough. Captain Dustin tracks the forecast and will proactively reach out if your trip looks unsafe. Reschedules and refunds are handled per our standard private-charter policy.
What does it cost?
Full-day Marquesas private charter is from $2,495 on our 30' Jeanneau. Marquesas + Boca Grande full-day is from $2,995. Up to 6 standard, 8 by arrangement. Captain, fuel, gear included.
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Ready for the atoll?

Send us your date and group size. We watch the weather and pick a calm day. If your flexibility window allows it, we'll match conditions to your trip.

Pick the sandbars you’d like to visit.

Your captain matches destinations to the wind, tide, and conditions of your booked day. Selections become a request the captain will confirm before your trip.

Pick at least one sandbar to see your recommended charter.
Or call (305) 906-2880 to plan with the team

Or email info@sixfinscharter.com with your date and group size.