About 12-15 thousand years ago retreating glaciers in Lithuania formed a moraine ridge. The top of this ridge is referred to as the Dutchman's Cap cliff. That is a the moraine ridge, rising 24 metres above the sea level. The Dutchman's Cap hill is constantly washed by the waves of the sea and descends to the seashore as a 16-18-metre-high cliff. There are no other cliffs on the Lithuanian seashore that are so high. The Dutchman's Cap cliff is included into the List of Natural Heritage of Lithuania. Ground waters erode the Dutchman's Cap cliff at the pace of 50 cm per year and the washed-away sand replenishes the beautiful beaches of Palanga and Giruliai. There were three cases, when in this location people found 23 000-year-old mammoth bones, two of which are exhibited at the Seaside Regional Park Visitor Centre.