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Anchorage

Marquesas Keys

A ring of mangrove islands 4 miles across between Key West and the Dry Tortugas, with a shoal-bound lagoon inside and sanctuary zones around the western keys.

West of Key WestLast checked 21 Oct 2026
Open in buoya
Extent
4 miles
Anchorage SW of Mooney Harbor Key
1–4 ft, reported
Boca Grande Channel
about 11 ft

Depths come from operators, the Coast Pilot, cruiser reports or a seabed model. This is not a nautical chart and does not tell you whether you will get through – use official charts and Local Notices to Mariners.

NESW
  • Sheltered
  • Partly
  • Exposed
  • No reliable report
Shelter by wind direction

Both rated anchorages here are open from the south – and they differ on everything else

Waterway Guide lists two places to lie in the Marquesas and rates them differently, so only what both say is coloured in. The shallow-draft spot by Mooney Harbor Key, in 4 to 9 feet, is rated open and exposed from the south. The deeper west-side anchorage, in 8 to 13 feet, is rated open and exposed from north-east right through south, and its listing adds the words "settled weather only". South is the one direction both name, and it is the only one shown. The Coast Pilot describes a reported anchorage in the lagoon south-west of Mooney Harbor Key, but that is where it lies, not which winds it keeps off, so it colours nothing.

The group

The Marquesas Keys are a ring of mangrove islands about 4 miles across on the west side of Boca Grande Channel, surrounded by a large shoal area. The northernmost key is the largest and has a sandy beach free of mangrove. In the middle lies Mooney Harbor, the group's central lagoon.

Anchorages and the lagoon

The Coast Pilot gives an anchorage south-west of Mooney Harbor Key with 1 to 4 ft reported, and a second one south-east of Mooney Harbor whose entrance carries 4 ft and is marked by pipes. Getting into the lagoon is the hard part: its main entrance was reported closed by shoaling in 1987, and the remaining entrance is restricted by a shoal and is a daylight job.

These are reported soundings, and the newest of them, on the lagoon entrance, is from 1987. Read the depths off the current chart.

Getting there

Boca Grande Channel, on the east side of the group, has about 11 ft; the current averages 1.2 kn and the flood sets north. The Coast Pilot says the channel is seldom used, and then by local boats of 6 ft draft or less. Ellis Rock, covered 7 ft, lies about 4 miles north-west. An area to be avoided covers the vicinity for tank vessels and vessels over 50 m.

Protected and restricted water

The Key West National Wildlife Refuge reaches out here from Key West, and the group is a Wildlife Management Area of the Florida Keys National Marine Sanctuary. That brings three restrictions with it: no-motor zones 300 ft around the three smallest keys on the west side, a no-access buffer zone 300 ft around one island on the west side, and idle speed only in the south-west tidal creek.

There are military danger zones in the vicinity as well, with bombing and strafing targets, under 33 CFR 334.620. Check them before you plan a route past the group.

Good to know

  • The lagoon: the main entrance to Mooney Harbor was reported closed by shoaling in 1987; the remaining entrance is restricted by a shoal and is daylight only.
  • Ellis Rock: covered 7 ft, about 4 miles north-west of the group.
  • Boca Grande Channel: about 11 ft, current 1.2 kn on average with the flood setting north, and seldom used – then by local boats of 6 ft draft or less.
  • Refuge: the Key West National Wildlife Refuge reaches here from Key West.

Rules that apply here

  • Wildlife Management Area: the group is a Wildlife Management Area of the Florida Keys National Marine Sanctuary, with access restrictions on and around the western keys.15 CFR 922 Subpart P, App. III
  • No-motor zones: 300 ft around the three smallest keys on the west side.15 CFR 922 Subpart P, App. III
  • No-access buffer zone: 300 ft around one island on the west side.15 CFR 922 Subpart P, App. III
  • Idle speed only: in the south-west tidal creek.15 CFR 922 Subpart P, App. III
  • Military danger zones: bombing and strafing targets lie in the vicinity.33 CFR 334.620
  • Area to be avoided: applies to tank vessels and vessels over 50 m.

Questions

Can I anchor at the Marquesas Keys?

The Coast Pilot gives an anchorage south-west of Mooney Harbor Key with 1 to 4 ft reported, and a second one south-east of Mooney Harbor whose entrance carries 4 ft and is marked by pipes. The group is a sanctuary Wildlife Management Area, so keep out of the no-access buffer zone 300 ft around one island on the west side, off the motor in the 300 ft zones around the three smallest western keys, and at idle speed in the south-west tidal creek.

How do I get into Mooney Harbor?

With difficulty. The main entrance to the lagoon was reported closed by shoaling in 1987, and the remaining entrance is restricted by a shoal and is daylight only. Depths change – check the current chart.

What is Boca Grande Channel like?

About 11 ft, with a current averaging 1.2 kn and the flood setting north. The Coast Pilot says it is seldom used, and then by local boats of 6 ft draft or less. Ellis Rock, covered 7 ft, lies about 4 miles north-west.

Sources & checks

Written by buoya editorial from the sources above. Every figure was checked against its source on 21 Oct 2026. Anything marked “reported” comes from cruiser reports, not from an official source. Found something wrong? Report a correction.