The ground floor (600 sq.m.) is used for special exhibitions.
Regional natural history from the Paleozoic to the habitat of today (First floor)
Beginning in the stairwell and on the first floor, regional natural history is presented in large show cases and by other exhibits, starting with historic finds of the Permian (280-245 mio. years). Saurian footprints, numerous fossils, models and taxidermal exhibits lead you through evolution, a journey taking you from the Paleozoic to the habitats of today. Particular emphasis is given to regional evolutionary and climatic conditions.
A huge, life-sized mammoth surrounded by reconstructions and finds from the Ice Age is an interesting center piece of this section. Dioramas illustrating aqueous life during marine periods offer an impression of the region's appearance while flooded by the ocean.
Regional beech forests and their denizens, like wild boars, red and roe deer, foxes and a large variety of birds are presented in a huge diorama.
From the Landgrave‘s cabinet of curiosities to a modern museum of natural history (Second floor)
The exhibition contains the precious historic pieces of the Landgraves collection. They are embedded among panels showing the varied history of the collection and the building "Ottoneum" as well as the accompanied early history of the natural sciences in Kassel. The first room contains the oldest preserved pieces: hunting trophies.
Well protected against light in a small chamber you can find the 16th century Herbarium Ratzenberger, one of Europe’s oldest systematic collections of plants, assembled in 1556-1592. Another showcase presents the teeth of narwhales, attributed with magic powers in former times.
The central room displays a reconstruction of an 18th century study room within the Ottoneum. Various ancient paintings and curiosities fill the walls and shelves. A nearby spacious chamber presents some preserved mummies of stillborn babies showing various malformations. They were objects for anatomical research and education in the early 18th Century.
The skeleton of the so called "Goethe Elephant" dominates the next room. In 1783 Johann Wolfgang von Goethe, the famous writer and scientist, lent the elephant skull to study it.
The probably biggest attraction is the hexagonal cabinet of the famous "Schildbach Wood-Library", encompassing 530 wooden volumes of different tree and shrub species. They were manufactured by Carl Schildbach, the Landgrave’s park administrator at the end of the 18th century. In 2012 the housing cabinet was new constructed as a documenta(13)-artwork by the US-American artist Mark Dion.
The nearby wooden cabinet with rock strata was a present of the copper-schist miners of the Richelsdorf area to Landgrave Friedrich II at the occasion of the opening of the Fridericianum in 1779. The last room presents the beginnings of the modern museum of natural history showing various animals as well as fossils.