The loggerhead sea turtle (scient. Caretta caretta) is the most important sea turtle species of Greece, which is strictly protected by the Greek laws. In Greece, two organizations are involved in the protection of sea turtles, namely ARCHELON and MEDASSET, actually doing a great job.
The leatherback turtle (scient. Dermochelys coriacea) is the largest reptile in the world, with its shell growing up to 250cm and its weight, sometimes, exceeding 900kg. Infrequent appearances of the species have been reported in Greece (and in Crete), while there has not been reported any case of breeding on Greek beaches.
The green sea turtle (scient. Chelonia mydas) has been met very rarely in the Greek seas and there are no indications for nesting on Greek shores. It is also found rarely off the Cretan seas and is the largest sea turtle with hard shell in the world.
The hawksbill sea turtle (scient. Eretmochelys imbricata) is an endangered sea turtle species found primarily in tropical seas. Some of them (very few) have been met in the open sea south of Crete and in other Mediterranean areas.