Il Grottino, which gives the dive site its name, is a short and easy passage through a large rocky cavity. The small cavern has its entrance at around 12 m and exits at approximately 5 m; it is about 6 m long and is particularly appreciated by divers because it provides shelter for numerous crustaceans. Large Mediterranean slipper lobsters and, occasionally, small European lobsters are often found inside. In front of the cave lies a semicircular shoal that reaches approximately 33 m where it meets the sandy seabed. Pelagic fish such as dentex and greater amberjack may be encountered around the outer shoal. Between the cave and the shoal, at around 15–18 m, a channel of sand and rocks is home to several octopuses and the moray eels that frequently share this habitat.