The Circus Maximus, the great hippodrome of Rome in the valley between the Palatine and the Aventine, originally laid out by the Tarquins; the principal venue of chariot-races and triumphal processions. Cicero cites the seating-rivalries of the equestrian order there at Pro Mur. 72-73 and the Circus is the locus of Verr. 2.1.154 in connection with the columns of the temple of Castor.