Marseille & the Calanques · France · Cave & cavern
La Grotte du CNRS
A cave mouth 10 metres high and 10 metres wide
Area photo: Karim saari · CC BY 4.0
A vast cave off Marseille whose entrance measures roughly 10 metres high by 10 wide and opens between 20 and 25 metres. The scale of the mouth is the point of the dive, and the depth means the time inside it is short and planned rather than open-ended.
Where it is and how deep
43.1730° N, 5.3871° EPublished position for this site.
The dive
The descent lands you in front of the entrance, which sits between 20 and 25 metres and measures around 10 metres high and 10 metres wide. It is a big enough opening that two divers pass through side by side without thinking about it, and the mouth itself is worth a moment before anyone moves in past it.
Inside, the site is a vast one and the depth outside sets the schedule: at 20 to 25 metres the no-stop time goes quickly, so the sensible plan is a short penetration within the guide's limits, keeping the daylight in the entrance behind you, then out and up the rock. The full extent of the cave is not published, which is another reason to treat the briefing as the boundary.
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 | Fair | Good | Good | Prime | Prime | Prime | Prime | Good | Fair | Fair |
Season follows Marseille & the Calanques: Jun–Sep is the main season; the mistral funnels down the Rhône valley and closes the offshore islands in any month.
Know before you go
- An overhead environment at 20 to 25 metres with no published survey of its extent; keep the entrance in sight and turn the dive on the guide's limit, not on your gas.
Sources
- La Grotte du CNRS — Scubago
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