Kau Keng Shan is a hill in Tuen Mun, the New Territories, Hong Kong and stands opposite from Castle Peak. Kau Keng Shan has a height of 507 metres (1,663 ft). During the Ming dynasty era (1368–1644), the area around the hill was used as a defence position against foreign forces, in particular the Portuguese, who had occupied Tuen Mun from 1514 to 1521.