CIRCUS, an edifice in use among the Romans, for the exhibition of chariot races, and other games. The Circensian games appear to have been introduced at Rome from a very early period. They were probably borrowed from the Etruscans. They were established by Romulus almost in the beginning of his reign, and they continued to retain their popularity till the latest times of the empire. The circus at first was a wooden enclosure in which the spectators stood, a few seats only being placed for the persons of principal distinction. The most ancient permanent circus at Rome of which we have received any account, was that built by Tarquinius Pris cus, in the valley Murcia, between the Aventine and the Palatine hills. This circus continued for a long time to be the only one in Rome. It obtained the name of the Cir cus Maximus, whether from its great superiority in size to those of a later date, from its being appropriated to the celebration of the greater games, or from its conse cration to the great gods. It was enlarged by Julius Cxsar, and rebuilt and richly ornamented by Augustus. Tiberius, Caligula, Claudius, and Nero, all made addi tions to it. It was farther enlarged by Trajan. Con stantine added to it some new porticos; and his son Con stens ornamented it with the great obelisk at present at the Lateran. Dionysius of Halicarnassus states the di mensions of this circus, as it was left by Augustus, to have been, for the length 3 stadia, the breadth 4 jugera, cor responding respectively to upwards of 3, and to about one and a half English furlongs. It could then contain about 150,000 persons. In consequence of the additions made to it previously to the time of the elder Pliny, it became capable of containing 260,000 spectators ; and an inscrip tion placed over the great gate subsequently to the alter ations made upon it by Trajan, bore that that emperor had rendered it adequate to receiving the whole Roman people. Of this superb edifice there remain only some very indistinct traces, which are level with the ground. The remembrance of it, however, is still preserved by tradition; the site of the building, which is at present oc cupied by gardens, and the cemetery of the Jews, being distinguished at Rome by the appellation Cerchi.
The other circuses at Rome were numerous and consi derable. The Flaminian circus was, according to Livy, founded by Flaminius, the unfortunate antagonist of Han nibal. This circus has been frequently noticed by an cient authors. Dion Cassius relates, that a Chace of cro codiles was exhibited in it by Augustus, when 36 of these animals were killed. On the site of this building, there are now erected the church and convent of Santa Cate rina the Funari, the two palaces of the dukes Mattel, with several other edifices. The only remains of this circus are ruins hid beneath the present pavement of the city, which is considerably raised in that part. Among these ruins, there still flows a considerable stream of had been employed anciently for the supply the circus.
A great part of what was the area of the Agonal cir cus is occupied by the modern Piazzi Navona. The at the northern extremity plainly follow, in their curved direction, the bend of the circular end of the ancient edifice.
One of the most remarkable of the Roman circuses was that which was begun by Caligula, and terminated by Nero. It appears to have been destroyed as early as the time of Constantine, since the former basilica of St Peter, founded by that prince, occupied the same situation as the present edifice, the right side of which rests upon the walls of the circus. The superb obelisk which at present ornaments St Peter's place belonged to that an cient edifice. From the exhibition given of the direction of the circus by Fontana (II Tempo Vatic. p. 245.) it seems to have been longer than the modern church, with the colonnade.
In some late excavations, there were discovered con siderable remains of a circus, which, as it is supposed, was begun to be built by Nero in the gardens of his aunt Do mitia, and was finished by Adrian. There were at the same time found several antique paintings.