Blue Cave
Dive site
A sea-level entrance in the limestone cliffs east of Derna town opens into a cathedral-sized cavern that floods with filtered blue light from submerged openings in its floor and walls. The cave extends roughly 40 metres back from the entrance at depths between 2 and 14 metres, with an air pocket at the rear that provides a natural resting point. The walls are covered in yellow cave sponges and tube worms. Swarms of anthias hover in the entrance zone where cave shadow meets open water. Grouper rest on the sandy cave floor. The site is visually spectacular with no technical equipment required for the main cavern. A deeper secondary passage at 14 metres continues under the cliff and requires proper cave configuration.
Conditions
Depth
2 to 22 m
Open water and up
Current
Variable
Can pick up on the edge
Visibility
22 to 30 m
Clearest in the calm season
Water
14 to 27°C
3mm wetsuit
Month by month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Water (°C) | 14 | 14 | 14 | 16 | 18 | 22 | 25 | 25 | 23 | 20 | 17 | 15 |
| Vis (m) | 12 | 12 | 12 | 15 | 20 | 22 | 22 | 22 | 20 | 15 | 12 | 12 |
| Current | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm |
Field journal
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