Mauritius · Mauritius · Cave & cavern
Cathedral
A guided cavern in the reef off Flic en Flac
Area photo: Diego Delso · CC BY-SA 4.0
A large cavern and cave system in the reef off Flic en Flac, on the west coast of Mauritius, and rated by Divezone as one of the best dive sites on the island. It starts at 18 m on a sandy base and runs down to 30 m, and the cavern itself is open only to divers under proper guidance. Marine life is described as abundant, but no source names the species you can expect.
Where it is and how deep
20.2790° S, 57.3691° EApproximate position — the dashed circle shows where the site lies; your operator's briefing has the mooring.
The dive
You dive it off Flic en Flac on the west coast, the stretch of shoreline Divezone singles out as a favourite among divers here. The base of the site is sand at 18 m with the cavern in the reef above it, and the system works deeper from there to 30 m. It is a cavern and cave system rather than a single arch you swim straight through, so the dive is a sequence of openings and chambers and the guide sets the order you take them in.
Entry into the cavern is for properly guided divers only, and that is the part of the dive to plan around: gas, order and an agreed way out before anyone goes in. The published description calls the area a photographer's dream, with abundant marine life and interesting features, and it is the structure that people come back for. No source lists which species are reliably resident here, so treat anything specific you are promised as your operator's own observation.
Marine life and season
The sources we used don't single out particular species here.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Fair | Fair | Good | Prime | Prime | Good | Good | Good | Good | Good | Prime | Good |
Season follows Mauritius: Cyclone season (Jan-Mar) can disrupt trips and cloud visibility; the trade-wind months of Apr-Nov give steadier, clearer conditions.
Know before you go
- The cavern is an overhead environment at 18-30 m and entry is limited to divers under proper guidance; agree gas turn points and the exit route with the guide before entering.
Dive videos
Diving in Mauritius 🇲🇺 "CATHEDRAL " · Kanayama mimi, Masami on YouTube
Questions divers ask
How deep is the Cathedral in Mauritius?+
The cavern begins at 18 m on a sandy base and the system runs down to 30 m, which puts it past the beginner range and makes Advanced-level experience the sensible minimum.
Can you swim inside the Cathedral cavern?+
Yes, but only under proper guidance. The cavern is an overhead environment, and the published description is explicit that entry is for divers who are properly guided rather than a free-for-all swim-through.
Sources
- Best Diving sites in Mauritius — Divezone
More dive sites in Mauritius
Reef
Shallow coral and a multitude of small reef fish
Wall
Steep walls and rock formations at about 34 m
Drift
A drift run deep to 26 m or shallow to 20 m
A 44 m fishing boat on sand at 30 m by Coin de Mire
Wreck
A fishing boat sunk for diving at 35 m, a reef since the 1980s
Wreck
A wreck sunk as an artificial reef at 43 m, rarely dived
Reef
A small rock outcrop on sand, 16 m at its deepest
Reef
The shallow part of L'Eveille, 5 to 19 m
Similar dives elsewhere
A 60 m wide cave mouth with sleeping nurse sharks inside
Two swim-through caverns, at 18-20 m and 28-30 m
Chimneys through the barrier reef that flood with daylight
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A cavern about 10 m high running from 15 to 30 m