The Oostvaardersplassen is a nature reserve in the Netherlands, covering about 56 square kilometres (22 sq mi). Despite having developed recently (it is in a polder which was only created in 1968) it already has international importance as a European wetland. The Oostvaardersplassen can be divided into two areas: wet and dry. In the wet area along the Markermeer, there are large reedbeds on clay, where moulting geese often feed.