In the district called by the name Circus Flaminius, stand the ruins of a vast range of buildings, the theatre, porticus, curia, and domus Pompeii. That these ruins, which are situated at the back of the church of S. Andrea della Valle, and are plainly those of a theatre, belonged to the Theatre of Pompey, is clear if the proofs given of the situation of the other two theatres in ancient Rome be admitted as sufficient. The place was so familiar to the Romans that we hardly ever find its locality indicated even in any such general terms as in campo Martio or juxta Tiberim, expressions commonly applied to other buildings of less note in the Campus Martius. The remains which are now left of these celebrated buildings are to be seen in the small piazza of S. Maria di Grottapinta behind the church of S. Andrea della Valle. They consist of ranges of travertine walls, converging to a centre, similar to those still visible in the interior of the Theatre of Marcellus and in the Coliseum, and are plainly the remains of the substructions supporting the cavea of a theatre. Further remains of piers and converging archways of peperino are visible in the cellars of the adjoining Palazzo Pio; and during some excavations made in 1837, a part of the outer walls of the theatre was discovered, with Doric half columns, and a Doric cornice. Most fortunately the ground plan, not only of the theatre, but also of the whole adjoining portico, is given upon some fragments of the Capitoline map. [Illustration: FRAGMENTS OF PIANTA CAPITOLINA. THEATRE OF POMPEY]