In the beginning of the 19th century there were still 748 artificial lakes in the Nové Město Manor. The biggest of them was Rozkoš. Its surface had 141 hectares. It had a short, solid dam, which held a big amount of water. In 1834 it was drained and only a brook, bearing the same name, remained. In 1966 to 1972 there was built a dam of considerably bigger size.