Secca di Mezzo Canale

Secca di Mezzo Canale is a submerged rocky pinnacle positioned in the channel between the island of Giannutri, the island of Giglio, and the Argentario promontory in Tuscany, reaching close to 100 metres depth. The shallowest point of the pinnacle, known as the "cappello" (hat), is the site's most distinctive feature and serves as a key lookout point for open-water species passing through.

The terrain is bare rock dropping steeply toward 100 metres. Below 35–40 metres the walls are colonised by large gorgonians and encrusting sponges, while around 50 metres the reef continues to deepen into less predictable territory. The bottom type throughout is rock, with relief that makes the site feel more like an open-water seamount than a coastal reef.

Marine life is rich across depth zones. The cappello draws large pelagics, while the gorgonian fans below 35–40 metres shelter basket stars (Astrospartus mediterraneus), groupers, sea bream, and lobsters. Sea urchins and starfish are also present on the rocky substrate.