Marseille & the Calanques · France · Cave & cavern
Grotte Arc-en-Ciel
A cave named for the colours the sunlight throws
Area photo: Karim saari · CC BY 4.0
A shallow cave off Marseille lying between 7 and 15 metres, named for the way the sun's rays break up as they penetrate it. The depth keeps the dive long and the overhead keeps it deliberate, and the catalogue puts it to intermediate and advanced divers.
Also known as Grotte arc en ciel.
Where it is and how deep
43.1967° N, 5.3631° EPublished position for this site.
The dive
Everything happens between 7 and 15 metres, so gas and no-stop time are not the constraints here; light and position are. The dive drops to the cave and works into it, and because the whole site sits inside that narrow band you can spend the bulk of a tank on it and still surface with a comfortable margin, which is unusual for the sites off this coast.
The name comes from what the sun does inside. Rays penetrate the cave and split into the play of light it is named for, which means the dive is worth timing for a bright day and a high sun. Beyond that there is nothing published about the site — no survey of how far the cave runs, no species list — so the guide's briefing is what sets where the dive turns.
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 with no published survey of its extent; stay within the guide's limits and keep the entrance in sight.
Sources
- Grotte Arc-en-Ciel — Scubago
More dive sites in Marseille & the Calanques
Cave & cavern
A cave-cathedral above a wall that drops to 40 m
Cave & cavern
A cave mouth 10 metres high and 10 metres wide
A plateau off Grand Congloué that ends in a beak
Wreck
Deep-certified only: the 1903 liner Liban off Île Maïre
A shallow orange freighter, a 1928 steamer and a Bf 109
Reef
Rock stacks shaped like wheels of cheese
One rock, from 35 metres up to a 5-metre finish
Wreck
A 70 m sailing ship on the bottom since 1897
Similar dives elsewhere
A 50 m training cavern at 17 m, 15 minutes from Moraira port
An air dome at the end of the first cave
A 30 m tunnel through the cliffs from 6 m, plus a cavern with an air bubble
Narrow swim-throughs and a small air pocket inside the rock, 18 m max