Croatia's Adriatic Sea draws many lovers of the underwater world. Undoubtedly the most attractive diving locations in the Adriatic are underwater cliff faces and reefs, caves and the wrecks of ships and aeroplanes. The clarity of its turquoise waters, the beauty of its depths, the variety of marine life, underwater cliff faces, reefs and caves, archaeological localities and the fascinating ship and aeroplane wrecks hidden at the bottom of the sea, are all part of its appeal.
Today, the number of registered and licensed diving centres exceeds 100, with the largest number being located in Istria and Kvarner, and in the area of Central Dalmatia. They cater for the inexperienced diver as much as for the experienced and offer courses which are both accessible and affordable. They also hire equipment and offer excursions that are within easy reach.
Sea temperature fluctuations throughout the year: in winter months temperature ranges from 7 to 10 °C, in summer months average surface temperature is from 21 to 26 °C, while the temperature at a depth of from 20 to 30 m (average diving depth) remains constant throughout the year, ranging from 16 to 17 °C.
The difference between high and low tide varies from 40 cm (Southern Adriatic and Dalmatia) to 1m at Istria. The Adriatic is a relatively calm sea, with no high waves or strong currents. Wave height ranges from 40 to 150 cm, to 4 to 5 m at the most in extremely adverse weather conditions on the open sea. Speed of sea currents is about 0.5 knots, although in certain places and in special weather conditions it can reach up to 4 knots.
Divers are required to purchase a HRS Divers Card from the Croatian Diving Federation, available through registered diving centres. The cost is 100 Kuna and is valid for one year. Individual diving is only permitted with the purchase of an individualpermit costing 2,400 Kuna per person.
There are zones where diving is prohibited even with individual permission. These are those zones under special protection by the Ministry of Culture, and diving in those areas may be allowed but only when accompanied by a diving guide from an authorized diving centre.
Areas where diving is prohibited: harbors, anchorages and areas of high traffic near military areas and boats underwater reserves, nature parks and other protected coastal and underwater areas, the Brijuni National Park and the Krka National Park, the islands of Palagruza and Jabuka
Areas where special licenses are needed: the Kornati National Park, the Mljet National Park.

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Diving in Croatia