Diocletian’s palace is one of the best preserved monuments of Roman architecture in the world. Cesar's palace was built as an appropriate interpolation of various contents of a luxury villa – a summer residence, resembling a scheme of a Roman military camp (castrum), divided into four parts by two main streets. In that design, the southern end of the palace was foreseen for the emperor, his residence and fitting national and religious ceremonials, while the northern part was for the emperor's guards – army, servants, storage space and similar.

The palace is rectangular in shape (around 215 x 180 m) with four large towers at the corners, four doors on each side and four smaller towers on the walls. The lower part of the walls is without any openings, while the upper storey is thrown open with a monumental arcade in the southern part and hallways with large arching windows on the other three sides. During the centuries, the Palace's residents, and then the residents of Split as well, adapted those spaces for their needs, such that the inside of the buildings, as well as the exterior walls with towers, were largely altered from their original appearance.