Mariners Cave Tonga
Vava'u, Tonga · Tonga
A fully submerged entry tunnel opens after 8 metres of horizontal swimming into an air chamber large enough to surface inside. Pressure changes from swell create a dramatic mist that fills and clears the cave with each wave cycle. The experience is genuinely unlike any other cave dive in the Pacific and requires a calm, confident buddy pair.
Conditions
Depth
3 to 12 m
Good for beginners
Current
Usually gentle
Can pick up on the edge
Visibility
20 to 30 m
Clearest in the calm season
Water
22 to 29°C
3mm wetsuit
Month by month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Water (°C) | 26 | 26 | 27 | 26 | 25 | 24 | 23 | 22 | 22 | 23 | 24 | 25 |
| Vis (m) | 15 | 15 | 15 | 15 | 20 | 20 | 20 | 20 | 20 | 20 | 15 | 15 |
| Current | Gentle | Gentle | Gentle | Gentle | Gentle | Gentle | Gentle | Gentle | Gentle | Gentle | Gentle | Gentle |
Your chances of seeing each animal
Scissortail Sergeant
Last confirmed Dec 20, 2025 · 56 records
Very likely
Most dives
Blue Linckia
Last confirmed Aug 20, 2025 · 21 records
Likely
About 6 in 10 dives
Pacific Double-Saddle Butterflyfish
Last confirmed Dec 20, 2025 · 16 records
Likely
About 6 in 10 dives
Humbug Dascyllus
Last confirmed Oct 3, 2025 · 23 records
Likely
About 6 in 10 dives
Humpback whale
Last confirmed Sep 4, 2025 · 4 records
Sometimes
About 1 in 3 dives
Fiji Tomato Anemonefish
Last confirmed Aug 20, 2025 · 13 records
Sometimes
About 1 in 3 dives
Spinner dolphin
Expected
Known here, not yet in recent logs
Sea snake
Expected
Known here, not yet in recent logs
Gear