Kosmosis housed in a wing of Palazzo Botta Adorno, built in 1693 when Luigi Botta Adorno bought two neighbouring homes and had them united with his own. The interiors were decorated and frescoed by Giuseppe Natali, with the guest apartment (referred to “the King’s”) being particularly impressive. This apartment occupied an area on the first floor that corresponds to the eight rooms now occupied by the museum on the ground floor.
Two rooms, decorated in the 700s, and part of Marshal Antoniotto Botta Adorno’s apartments, were spared in a renovation carried out in the 800s. They consist of a large reception room and adjoining bedroom with an alcove., It was here that Napoleon Bonaparte was accomodated when he came to Pavia on an official visit in 1805. The frescoes are attributed to the Cremonese artist Giovanni Angelo Borroni.
The building, completed towards the end of the 700s, was elaborately decorated with gilded stucco and precious sculptures, and filled with mirrors, lamps, furniture and other décor.
The Botta Adorno’s drawing room was an important reference point in the social and cultural life of Pavia. Lazzaro Spallanzani was a regular guest because of his connection with the Marquis’s daughter, Clementina Botta. Over the course of the 800s, the building hosted a number of illustrious guests. In addition to Napoleon, these included Francis I of Austria, Ferdinand of Habsburg, Joseph Radetzky and Victor Emanuel II of Savoia.
When the last descendent of the Botta Adorno family died, the complex was acquired by the university in 1887 to use as premises for its science institutes. The building underwent substantial enlargement and restructuring. The neoclassical façade was decorated with metopes representing scientific themes in 1892 by Leopoldo Mansueti and Alessandro Maciachini. The entrance, situated at the present-day street number 10, was designed as a gallery leading from the square outside into the garden.
Halfway down the entrance gallery, on either side, are two symmetrical monumental staircases in neoclassical taste. Two new wings were added to the building, including two semi-circular auditoria and the two minarets, designed to act as ventilation stacks for the laboratories and the dissection rooms.
Outdoors, behind the building, can be seen the aquarium built in 1913 on the initiative of Camillo Golgi, with ponds and incubation basins used for teaching and for the study of fish reproduction.