Hessisches Landesmuseum Darmstadt is a large multidisciplinary museum in Darmstadt, Germany. It was founded in 1820 with the donation of the collections of the ruling family of the local princely state, which ended as the Grand Duchy of Hesse. The current main building was begun in 1897, and a large extension in 1980. After major renovations from 2007 onwards, it reopened on September 13, 2014. It also features an important natural history collection, with for instance fossils from the nearby Messel pit and a historic American mastodon purchased by the Darmstadt naturalist Johann Jakob Kaup