As of today, peak season now, through ~June 30. Earth Exhibit tracks the live conditions and flags it the moment it is on.
The Great Blue Hole is a giant marine sinkhole near the center of Lighthouse Reef, a small atoll approximately 70 km off the coast of Belize.
Measuring 318 meters across and 124 meters deep, it is the world's largest known feature of its kind.
The hole formed as a limestone cave system during Quaternary glaciation periods when sea levels were far lower, with stalactite analysis dating formation episodes to 153,000, 66,000, 60,000, and 15,000 years ago.
When rising seas flooded the cavern, the roof collapsed to create the current sinkhole.
Interior ledges at 21, 49, and 91 meters mark distinct flooding stages.
Massive stalactites and stalagmites up to 12 meters long hang from overhangs at depth.
The rim teems with Caribbean reef sharks, nurse sharks, groupers, and giant barrel sponges.
Jacques Cousteau brought the Calypso here in 1971 and declared it one of the world's top five dive sites.
The Great Blue Hole is part of the Belize Barrier Reef Reserve System, a UNESCO World Heritage Site since 1996.
Where to see it
A taste of where to see it. The full map, exact coordinates and the best timing for each spot live in the app.
| Viewing spots |
|---|
| Great Blue Hole, Lighthouse Reef Atoll |
| Half Moon Caye, Lighthouse Reef |
| + 1 more spot, with exact coordinates and timing, in the app → |
This is the short version
This page shows a taste. The app has the full list of where to see this, the exact timing, and live conditions for 1,000+ natural phenomena worldwide, so you know the moment one is genuinely worth the trip.