Diocletian Palace is one of the best preserved monuments of the Roman architecture in the world. The Emperor's Palace was built as a combination of a luxury villa - summer house and a Roman military camp (castrum), divided into four parts with two main streets. Southern part of the Palace was, in this scheme, intended for the Emperor's apartment and appropriate governmental and religious ceremonies, while the north part was for the Imperial guard - the military, servants, storage etc. The Palace is a rectangular building with four large towers at the corners, doors on each of the four sides and four small towers on the walls. Over the centuries the Palace inhabitants, and later also the citizens of Split adapted parts of the palace for their own requirements, thus the inside buildings as well as the exterior walls with the towers significantly changed the original appearance, but the outlines of the Imperial Palace are still very visible.