A triumphal arch. These arches were peculiar to the Romans, and were usually detached structures built across the principal streets of the city, and, according to the space of their respective localities, consisted of either a single archway, or of a central one for carriages, with two smaller ones on each side for foot-passengers, which sometimes had side communications with the central arch. Sometimes there were two arches of equal height, side by side. Each front was ornamented with trophies and bas-reliefs, which were also placed on the sides of the passages. Both faades had usually columns against the piers, supporting an entablature, surmounted by a lofty attica, on the front of which was the inscription, and on the top of it bronze chariots, war-horses, statues, and trophies. The triumphal arch recalls its original, the city gate, in the concentration of ornament on the faades, while the sides, which in the city gate are buried in the wall, are comparatively plain.
Stertinius is the first upon record who erected anything of the kind. He built an arch in the Forum Boarium, about B.C. 196, and another in the Circus Maximus, each of which was surmounted by gilt statues. Six years afterwards, Scipio Africanus built another on the Clivus Capitolinus, on which he placed seven gilt statues and two figures of horses; and in B.C. 121, Fabius Maximus built a fourth in the Via Sacra, which is called by Cicero the Fornix Fabianus. None of these remain, the Arch of Augustus at Rimini being one of the earliest among those still standing.
There are twenty-one arches recorded by different writers as having been erected in the city of Rome, five of which still remain: (1) Arcus Drusi, which was erected to the honour of Claudius Drusus on the Appian Way.
(2) Arcus Titi, at the foot of the Palatine, which was erected to the honour of Titus after his conquest of Iudaea, but does not appear to have been finished till after his death, since in the inscription upon it he is called Divus, and is also represented as being carried up to heaven upon an eagle. The bas-reliefs [p. 118] [figure in text: Arch of Constantine at Rome.] of this arch represent the spoils from the Temple of Jerusalem carried in triumphal procession. This arch has only a single opening, with two columns of the Roman or Composite order on each side of it.
(3) Arcus Septmi Sevri, which was erected by the Senate (A.D. 207) at the end of the Via Sacra, in honour of that emperor and his two sons, Caracalla and Geta, on account of his [figure in text: Arch of Septimius Severus.] conquest of the Parthians and Arabians.
(4) Arcus Gallini, erected to the honour of Gallienus by a private individual, M. Aurelius Victor.
(5) Arcus Constantni, which is larger and more profusely ornamented than the Arch of Titus. It has three arches in each front, with columns similarly disposed, and statues on the entablatures over them, which, with the other sculptured [p. 119]
ornaments, originally decorated the Arch of Trajan. [figure in text: Arch of Augustus at Aosta.]
See Burn, Rome and the Campagna; Middleton, Ancient Rome in 1885; id. Remains of Ancient Rome 1892); and the article Architectura.