Cyclades dive sites

Kleftiko is accessible only by boat, located on the remote southwestern coast of Milos with no road access. Dive boats depart from Adamas harbour, with the journey taking 45 to 60 minutes depending on sea conditions. The site is sheltered from the prevailing meltemi winds during summer, making it more reliably diveable than many exposed Cycladic sites. Diving is typically conducted from anchored boats with entries near the cave mouths. The seabed ranges from 5 to 30 metres, with most cave and arch features between 5 and 20 metres.

Kleftiko's formations are the result of volcanic activity that shaped Milos over millions of years. The island sits on the Hellenic Volcanic Arc, and the white cliffs at Kleftiko are composed of volcanic tuff and pumice sculpted by wave erosion into towers, arches, and sea caves. Underwater, the same geological processes have created tunnels, overhangs, and swim-throughs with mineral staining in greens, oranges, and reds from volcanic deposits. This combination of volcanic geology and marine erosion has produced formations found nowhere else in the Cyclades.

Kleftiko means place of thieves in Greek, named for the pirates who used its hidden sea caves as a base during the medieval and Ottoman periods. The caves provided concealment from naval patrols, with narrow entrances opening into spacious chambers where ships could be hidden. Some caves still show evidence of human use. Today, the site is one of the most visited natural attractions on Milos, though the underwater cave systems remain far less explored than the surface formations, offering divers a genuine sense of discovery.

Santorini's caldera was formed by one of the largest volcanic eruptions in recorded history around 1600 BC, the Minoan eruption. Diving inside the caldera means descending along the submerged inner walls of this ancient volcano, past layers of volcanic rock and pumice that tell the geological story. Active thermal vents near the Kameni islands release warm water and mineral deposits, and the volcanic substrate creates unique rock formations found nowhere else.

Open Water divers can enjoy several sites at 10 to 18 metres around the caldera. The deeper wall dives reaching 30 metres require Advanced Open Water certification. The caldera is sheltered from most wind directions, making conditions generally calm. Some sites near Nea Kameni volcano are restricted, and all diving should be arranged through licensed Santorini dive operators.