Local club log with a drift from la Grotte du CNRS, red coral, octopus, and safety support.
Boat-access Marseille cave with coral, lobsters, and eels.
Boat-access Marseille cave with coral, lobsters, and eels.
Boat access and the overhead entrance make a local operator the practical way to dive it.
la Grotte du CNRS is a boat-access cave dive off Marseille that opens into a broad overhead entrance and a network of walls, cavities, and enclosed passages. The site is known for colorful sponges, anemones, red coral, lobsters, moray eels, and octopus, with a profile that rewards calm-day planning and careful buoyancy.
Conservative baseline from public research. No community dives logged yet.
Depth range, seasonality, and planning context.
Reported Depth
20m - 25m
Depth Note
Entrance depth reported between 20 and 25 m.
Best Season
Year-round, with calm-weather windows preferred.
Typical Conditions
Overhead cave with a deep entrance, variable visibility, and a calm-day preference; more technical than an open wall.
Hazards, restrictions, and access requirements.
Key Hazards
Safety Notes
This is an overhead cave environment; plan gas and navigation accordingly and use appropriate cave-diving procedures and equipment.
Access Restrictions
Overhead cave diving only, with appropriate training and operator support.
Community notes to help plan your visit.
Scuba Diving
Advanced scuba site with an overhead cave entrance and wall/cavity exploration.
Community dive logs and visit reports for this site.
Average conditions based on logged dives & visits.
Planning answers for access, conditions, timing, and site logistics.
Last Updated
Research Sources
Local club log with a drift from la Grotte du CNRS, red coral, octopus, and safety support.
CIP Marseille center page with boat diving, facilities, and year-round season.
Official Mediterranean diving inventory listing la Grotte du CNRS as a level-2 natural site with low usage.
Independent Marseille dive guide describing la Grotte du CNRS as a large cave with a coralline wall.
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