The museum operates in the Magna Curia Palace, also known as Bethlen Castle, an architectural monument located at the foot of Deva Fortress, included in the List of Historical Monuments.
In 2006, the restoration process was completed, which was meant to restore as much as possible the former splendor of the palace, making it a point of attraction for visitors and emblem of the city.
Since 2012, in the courtyard of the Magna Curia Palace, there is an open-air Lapidarium that houses a collection of monuments, belonging to the eras: prehistory, Dacian and Roman, with source from archaeological research in Baia de Cris, the Dacian Citadels in the Orastie Mountains, Ulpia Traiana Sarmizegetusa, Micia, Germisara, Aquae or from accidental discoveries. The Lapidarium area was later completed with two other buildings that house Roman monuments grouped on two major themes "Roman Civil Architecture and Roman Funerary Architecture".
The predominant pieces in the museum's patrimony are constituted in collections of prehistory, Dacian, Roman, early medieval, medieval, a collection of knives and firearms, modern and contemporary military equipment, collections with pieces of modern and contemporary history. To these are added a collection of art and an ephemeris, as well as a collection of natural sciences.