This submerged volcano is over 400m high and its summit is eight metres below the surface. It was formed at the collision point of the African and European tectonic plates and has disappeared under water since it surfaced during the 19th century. Underwater volcanoes can be biodiversity hotspots as they bring up nutrients from the sea bed and offer a place in which fish can shelter.
As with all volcanic hotspots there is an abundance of life.
This sea mound formed an island in the 1900s before the soft volcanic rock was erroded - now its summit is 6-8m below the surface. Legend has it that it was bombed when mistaken for a submarine. Makes for an unusual dive hazard.