The halls on the ground floor hosted a collection of antiques and a „gallery with modern statues“. This gallery consisted of a hall with copies of antiques made out of marble, bronze and plaster and cabinets with displayed statuettes, cameos and vases.
Additionally cabinets with medals, automatons, timepieces and cork reproductions of Roman buildings were on display.
The Beletage domiciled the Hessian county library. Like a splendiferous gallery it reached from one main wing to the other and could actually store over 100.000 books. Both side wings on the upper floor gave access to an etching cabinet,  a hall for cartographies and a room for calligraphy, as well as rooms displaying scientific instruments.
After 10 years of construction, on May 23rd 1779, the opening of the first public museum building was celebrated.

Almost thirty years later the youngest brother of Napoleon, Jérôme Bonaparte, converted the museum into the „Palais des Ètats“, a house of parliament with representation rooms. In 1813, the building was turned back into a museum, but then no longer followed the idea of art and science penned by the dynasty, instead now fully concentrated on its museal collection.
But due to the Prussian leadership in 1913 this public service was also shut down and the Fridericianum lost its museal mission. Almost all the collection pieces were transferred to Berlin, the Prussian centre. Until it went up in flames in 1941 it was a library.

A good decade later the ruins of the Fridericianum became the cultural heart of the first documenta exhibition.

It is of major interest that it is used since 1988 as a space for permanent and temporary art shows which take place inbetween the world exhibition documenta.