Sea caves of Tonga
Cathedral Cave ('Eua)
- Max depth30 m
- CertificationCavern
Diving and fills
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The dive
Through the entrance you come into an amphitheatre about 100 m long and 50 m wide, where daylight falls in through holes in the ceiling. Several tunnels lead off from the main chamber into the rock.
1 earlier accident or incident has been reported at this cave. Read what happened ↓
Profile and sections
Through the entrance you come into an amphitheatre about 100 m long and 50 m wide, where daylight falls in through holes in the ceiling. Several tunnels lead off from the main chamber into the rock.
The chamber was found in 2001 and is called the largest underwater cave in the South Pacific.
Practical: freedivers visit with Blue Water Retreat on 'Eua when conditions allow. In 2019 divers went there on a whale-watching boat.
- Depth and profile
- Entrance at 28 m, deepest point 30 m. A chamber of ~100 by 50 m, with tunnels leading off the main chamber.
- Configuration
- Large, well-lit chamber at depth: recreational gear with a torch, within your no-deco time; not the side tunnels without cave training (estimate).
Who can dive where
- At least Cavern
- Configurations: Backmount / twinset / Sidemount / CCR / Small cylinders / no-mount (speleo sumps)
- Goes down to 30 m (trimix or deco may be needed)
This is how the planner decides who in your team may dive this cave. Rules your own trip adds (organizer, a mail, the AI) show with your trip.
How to get there
Off the north coast of 'Eua, by boat only. A dive operator taking scuba divers here now is not confirmed (see the warning).
Around Cathedral Cave ('Eua)
FillsNo fill station known nearby
News
All (1)
Accidents and incidents
What happened at this cave before, with the sources. No names are given; read it as a lesson for your own planning.
- On 11 August 2019 a German diver (40) disappeared after a dive in the cave from a whale-watching boat. According to the guide she had left the group and ascended earlier; her weightbelt and later a fin were found on the chamber floor. The search was called off in worsening weather and what happened remains unexplained.
Access and rules change: check what applies locally right before your trip. Source: GDELT Project and the news feeds of diving magazines. Search for more news ↗ Searched automatically, last on 5 Nov 2026.
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