The Collector's museum was a private museum in Knowhere owned by the Collector. The building is multiple stories tall, although the main point of interest is on the ground floor[UK]1st floor[US]. Prior to its destruction, the museum held various objects and specimen, including Howard the Duck, Cosmo, and the Aether.
In 2014, the Guardians of the Galaxy traveled to the museum with the Orb. Carina, the Collector's Krylorian slave, attempted to seize the Orb, triggering a huge explosion within the museum. During the Infinity War, Thanos attacked the museum while looking for the Reality Stone.