The Märkische Schweiz Nature reserve is the smallest and oldest (since 1990) in the state of Brandenburg. Its heraldic animal is a dragonfly, one of the many species that populates the diverse landscape with small lakes, pools and rivers, ravines, steep slopes with dry grasslands. This also provides a habitat for about 250 bird species, including the black stork and sea eagle, beavers, otters and many mosquitoes. The main town is Buckow, the only recognised spa town in Brandenburg.