The Greek theater was a large, open-air structure used for dramatic performance. Theaters often took advantage of hillsides and naturally sloping terrain and, in general, utilized the panoramic landscape as the backdrop to the stage itself. The Greek theater is composed of the seating area (theatron), a circular space for the chorus to perform (orchestra), and the stage (skene). Tiered seats in the theatron provided space for spectators. Two side aisles (parados, pl. paradoi) provided access to the orchestra. The Greek theater inspired the Roman version of the theater directly, although the Romans introduced some modifications to the concept of theater architecture. In many cases the Romans converted pre-existing Greek theaters to conform to their own architectural ideals, as is evident in the Theater of Dionysos on the slopes of the Athenian Acropolis. Since theatrical performances were often linked to sacred festivals, it is not uncommon to find theaters associated directly with sanctuaries..