Reef Explorers

Finistère (Brest, Crozon & Glénan)

Diving in France

12 documented dive sites, 3 of them for Open Water divers. Known for dolphins, seals and rays.

Best months
Jun–Sep
Water
10–17 °C
Levels
Open Water, Advanced, Experienced
Nearest airport
BES

When to go

Pick a month: the diving season, from published sources, and the typical weather.

Pick a month

  • Best
  • Good
  • Possible
  • Closed
  • Not documented yet

Finistère (Brest, Crozon & Glénan) in October

Good season
Sea
16 °C
at the surface
Air
17 °C
13 °C at night
Rain
140 mm
one of the wettest months
Wind
21 km/h
on average

Typical weather, not a forecast: averages for 2021–2025 (air, rain, wind) and 2023–2025 (sea), data from Open-Meteo (ERA5 / Copernicus, Météo-France). Covers an area of roughly 10 to 25 km around the destination.

Operator seasons: Arimair (Brest roadstead) March–December; CIP Glénan 1 April–31 October 2026; Ouessant Subaqua April–November (enezgreen) / May–November (MAB France). Jun–Sep is shown as best because every sourced centre is open and the water is warmest (August average 16.7 °C, seatemperature.org). Jan–Feb and Dec are shown as possible (only roadstead clubs; no source says all diving stops). March is shown as possible: only Arimair is open and the water is coldest (10.1 °C average).

Source: tourismebretagne.com

Marine life

When the big encounters happen, month by month.

SpeciesJanFebMarAprMayJunJulAugSepOctNovDec
DolphinsSource: parc-marin-iroise.fr
  • Peak season
  • Seen

Dolphins: All year

Also reported here, season not documented yet:

  • Seals
  • Rays
  • Crustaceans
  • Octopus
  • Conger eel
  • John dory

Where is Finistère (Brest, Crozon & Glénan)?

View on OpenStreetMapLocation: Roadstead of Brest (Wikipedia)Map: Natural Earth
Nearest airport
BES

Finistère (Brest, Crozon & Glénan): frequently asked questions

When is the best time to dive Finistère (Brest, Crozon & Glénan)?
The best months to dive Finistère (Brest, Crozon & Glénan) are Jun–Sep. Operator seasons: Arimair (Brest roadstead) March–December; CIP Glénan 1 April–31 October 2026; Ouessant Subaqua April–November (enezgreen) / May–November (MAB France). Jun–Sep is shown as best because every sourced centre is open and the water is warmest (August average 16.7 °C, seatemperature.org). Jan–Feb and Dec are shown as possible (only roadstead clubs; no source says all diving stops). March is shown as possible: only Arimair is open and the water is coldest (10.1 °C average).
Is Finistère (Brest, Crozon & Glénan) good for beginner divers?
Yes, partly: 3 of the 12 dive sites we document are suited to Open Water divers, including Le Dellec, Les 4 Pompes and Le Mustang. The others need more experience or a higher certification.
What is the water temperature in Finistère (Brest, Crozon & Glénan)?
The water is usually between 10 °C and 17 °C over the year.
What marine life can you see in Finistère (Brest, Crozon & Glénan)?
Divers regularly see dolphins (all year), seals, rays, crustaceans, octopus and conger eel.
How do you dive Finistère (Brest, Crozon & Glénan)?
The nearest airport is BES.

About this page

Seasons and marine life come from the sources below. Site levels and depths marked as estimated come from our original catalogue and are being checked one by one. Conditions change: always confirm with a local dive centre.

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Photo: Sarah Lee on Unsplash
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