The Drusku castle mound (247 metres above the sea level) is a national monument of archaeology located in a hilly area on the northern shore of Lake Pilskalna. To reach the castle mound you have to walk along the nature trail starting at the Veclaicene administration building at Korneti. The main natural values in the surrounding of the castle mound is the European Union protected forest biotopes, coniferous forests rich in herbaceous plants, old or natural boreal forests, forests of slopes and ravines.
The Drusku castle mound is specific because of its south-western slope, which towards the lake is extraordinary steep and high, rising about 90 m above the water level of the lake.
