Great Blue Hole

Best months: Jan, Mar, May–Dec

Protected Area

Blue Hole

Why dive here

With 213+ marine species recorded in the area - including barracuda, dolphins, eagle rays, nurse sharks and sea turtles - Great Blue Hole offers some of Lighthouse Reef's richest cave diving. Water ranges 27-30°C, warmest August, September, October.

Marine lifeBarracuda, Dolphins, Eagle Rays, Nurse Sharks and Sea Turtles · 213+ species recorded

Water27-30°C · warmest August, September, October

CharacterCave dive

StandoutExceptional marine biodiversity

The Great Blue Hole, smack in the middle of Lighthouse Reef, is one of those places you just have to tick off. We're talking serious bragging rights here, but honestly, it’s more than just a bucket list item. Dropping in, the sheer scale hits you – a perfect circle of deep blue in a sea of turquoise. The real show starts around 40 metres. That’s where you’ll find the giant stalactites, remnants from when this was a dry cave during the last ice age. We love the feeling of swimming amongst these massive ancient formations, they just dwarf you. It’s dark down there, the light fading fast, and it feels genuinely prehistoric. Keep an eye out for the reef sharks that cruise through the deeper sections; they’re often curious, though not overly interested in divers. Visibility is usually good, but the light changes dramatically as you descend, shifting from vibrant blue to a deep, inky indigo. It’s a dive for those who appreciate geology as much as marine life, and it definitely suits divers comfortable with depth and a bit of overhead environment. Our insider tip? Go early in the morning to beat the crowds, and try to time your descent to catch the best light filtering through the opening.