The second deepest blue hole in the world. Long Island, Bahamas.
Imagine a salt-water swimming pool, with warm, calm waters that run 203 metres deep, populated by snapper, jacks and colourful tropical fish, patrolled by a school of silver-plated tarpon and visited by curious rays, turtles and tiny seahorses. An underwater cathedral festooned with light and life. This will be your classroom, your playground, your sanctuary.
At the surface the blue hole is 45 by 55 metres, before narrowing to 25 by 35 metres for a series of balconies at a depth between 10 and 15 metres. It then opens out into the second largest underwater chamber: a cavern with a diameter of at least 100 metres — we still haven't found all the edges at depth.
It is still unknown exactly how Dean's Blue Hole was formed, as it is almost twice as deep as any of the other blue holes in the Caribbean that were formed when limestone chambers (cenotes) caved in from above. One hypothesis is that a much deeper cave slowly moved upward as its ceiling eroded away.
A resident school of tarpon hangs in the shadows at 20 metres, and friendly turtles sometimes come into the hole for a break from the ocean currents. In 2026 three of these became permanent tenants for the season, becoming accustomed to and friendly with freedivers.
The coral caves and sand banks on the side of the entrance harbour all kinds of tropical reef life, from tiny shrimps up to groupers, snappers and moray eels.
Swell and wind don't reach in. The rim closes overhead and the light narrows to a single bright disc.
Search for flights with Nassau (NAS) as your destination. From Nassau, two airlines fly daily to Deadman's Cay Airport (LGI) on Long Island — Bahamasair and Southern Air.
Makers Air is a company that won't show up on travel searches, but flies three times a week (Tuesday, Thursday and Sunday) direct from Fort Lauderdale, Florida to Stella Maris (SML) in the north of the island.
Important: if you fly in via Nassau and your plane makes a stop at Stella Maris (SML), do not get off — stay on to Deadman's Cay, which is five to ten minutes from the blue hole. Stella Maris is about an hour's drive away, so allow for the transfer if you come in on Makers Air.
There are many great Airbnbs close to Dean's Blue Hole, as well as private villa rentals such as Harbour Breeze. You will probably also need a car rental, as there are distances between the accommodation, the blue hole, and the restaurants and supermarkets.
The Bahamas tourism board's Long Island guide is a good source of general travel information.