Sorry, can't remember the name. This one is on the west side of the island, in the section of the Egadi's marine sanctuary where the protection of the environment is more strictly enforced. Here only local residents are allowed to navigate close to the coast (while everybody else should keep at a little less than half a mile from it).
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/78722206@N00">Fulvio Spada</a> from Torino, Italy
CC BY-SA 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/lfphotos/15104566288/">One of Marettimo's 400+ grottos</a>