Excavation of a small amphitheater named "Tondo di Zagarolo" in the vicinity of the cutting of Cavamonte, where the Prenestina curved toward the north in the direction of Gallicano. The monument had already been identified by the sketches of Andrea Palladio, according to which the amphitheater was of two levels formed by concentric rings connected by radial sectors. The excavations have brought to light the internal ring which delineated the arena, and the remains of the radial walls that formed rooms covered by barrel vaults. Beyond this were discovered subterranean rooms arranged along the orthogonal axis of the amphitheater and connected to the center of the arena.