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Hotels, dive operators, gear, and how to get here are on the Capo Carbonara location page.
Overview
The largest underwater cave in the Mediterranean, cut into the limestone cliffs of Capo Caccia just north of Neptune's Grotto near Alghero. A main tunnel runs roughly 300 metres through the headland, linked by around ten arches and side passages between the surface and 35 metres. Walls and ceilings are crusted with red coral (Corallium rubrum) and clusters of yellow Leptopsammia pruvoti, while dusky groupers, congers, Mediterranean morays and spiny lobsters shelter in the dark recesses. Summer visibility regularly tops 30 metres.
Briefing note
Overhead environment inside the Capo Caccia-Isola Piana marine protected area; deeper tunnel penetration requires cavern/cave training, a guide and a torch. Corallium rubrum is protected - no collection.
What you'll see
6 species curated- year-roundRed coralPeak: May · Jun · Jul · Aug · Sep · Oct
- year-roundYellow cave coralPeak: May · Jun · Jul · Aug · Sep · Oct
- year-roundDusky grouperPeak: Jun · Jul · Aug · Sep · Oct
- year-roundEuropean congerPeak: May · Jun · Jul · Aug · Sep · Oct
- year-roundMediterranean morayPeak: May · Jun · Jul · Aug · Sep · Oct
- year-roundEuropean spiny lobsterPeak: May · Jun · Jul · Aug · Sep · Oct
Conditions
| Month | Water | Visibility | Current |
|---|---|---|---|
| Jan | 14–15 °C | 12–20 m | mild |
| Feb | 13–14 °C | 12–20 m | mild |
| Mar | 13–15 °C | 15–22 m | mild |
| Apr | 14–16 °C | 15–25 m | mild |
| May | 16–18 °C | 18–28 m | mild |
| Jun | 19–22 °C | 20–30 m | mild |
| Jul | 22–25 °C | 25–35 m | mild |
| Aug | 24–26 °C | 25–35 m | mild |
| Sep | 22–25 °C | 20–32 m | mild |
| Oct | 19–22 °C | 18–28 m | mild |
| Nov | 17–19 °C | 15–25 m | mild |
| Dec | 15–16 °C | 12–20 m | mild |
Season calendar
Peak season highlighted · current month outlined
Gear for this site
Beyond the basic kit- Dive light — The 300 m main tunnel and side passages stay dark even in summer; a torch is needed to light the red coral and read the overhead.
Next step
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