There are excellent facilities along all coastlines of the mainland and particularly in the islands.
Most major hotels can help with arrangements.
Speed boats are also available for hire. Independent scuba diving is strictly forbidden, in order to guard against the pilfering of underwater antiquities. Divers may only venture out under the auspices of a recognised diving school. Snorkelling is permitted, however, and is possible practically anywhere. Greek waters offer good fishing, particularly during the summer and autumn.