Forum Romanum | Home of the Vestal Virgins 
This used to be a building with about 50 rooms on three floors. The most important remains are those of the central inner court, which you see on this picture. The statues that were in better shape than these (e.g. with heads on them) have been moved towards the Museo Nazionale Romano in Rome.
Behind, the remains of the home itself. It's actually in pretty good shape, but can not be visited.