The Museum for Nature and Man is a gift by Grand Duke Paul Friedrich August to Oldenburg. The exposition begins with a kind of "Oldenburg in section" - a large rectangular block, covered with moss and consisting of several layers of marshy soil. At opening the museum, its exposition was limited to the collection of insects and birds. It has expanded over the past 200 years: archaeological finds, ethnographic collections, flora and fauna of Oldenburg. The pride of the museum is the aquarium, which presents the inhabitants of the Hunte river. The concept of the museum has also changed: originally it was the history of the north-eastern Germany in terms of science, and now it is evolution of the nature of this land as affected by man.