Mljet National Park is located on an island, with an area of 5375 hectares. Most of the island is covered with forest, considered to be the most beautiful and most preserved in the Mediterranean. Also, numerous endemic plants can be found on the island of Mljet. The island is rich with small mammals, such as rabbits, dormouse, bats, hedgehogs... Fallow deer were brought to the island after the Second World War. Among the other species are various birds, lizards and snakes, and invertebrates found in caves. Most interesting to see are the small lakes filled with sea water and packed with shells. In the middle of one lake there is a small island with a monastery standing on top.