Medvidina cave on the island of Biševo, not far from Komiža, is very interesting geomorphologically. Its entrance on the sea surface is relatively large-sized but these dimensions gradually decrease towards its interior. At its end, the cave is very narrow and low, and its complete length of 160 meters ends with a little beach. Besides its attractiveness this cave was significant as the ideal breeding ground of one of the most endangered mammals in the world - the Mediterranean monk seal (Monachus monachus), a very rare species of seal. Today the Mediterranean monk seal has practically disappeared from the Adriatic and can be rarely seen, but we should hope that very soon the beach at the end of the cave will once again be the cradle of little seals.
Modra Spilja (Blue Cave) is located on the island of Bisevo, not far far from Komiza (town on the island of Vis). This cave is geomorphologically interesting and presents a typical karst form. A special attraction and unique experience are the specific light effects created by the refraction of sunlight. Today it is a tourist attraction.