11 cave dive sites in United Kingdom.
By area: Argyll and Bute (2), England (2), Scotland (1) and Warwickshire (1).
Recorded maximum depths range from 5 m to 50 m (10 of 11 sites have a depth).
By level: 5 beginner, 2 intermediate and 2 advanced.
Species confirmed at these sites by diver sightings (three or more independent divers) or by two or more independent sources, with the number of sites each is confirmed at.