Close to the ruins of the Temple of Concord stands the triumphal arch of Septimius Severus, composed of three archways of Pentelic marble. The side archways are connected with the central archway by small openings in the intervening walls, and the arched interiors of all three are decorated by square coffers with rosette ornaments. On each side stand four columns of Proconnesian marble with Composite capitals, on the pedestals of which are bas-reliefs representing figures of barbarian captives clothed in breeches and wearing the chlamys and Phrygian cap, and conducted by Roman soldiers wearing the lacerna. The spandrils of the arches are ornamented with the usual figures of Victory and symbols of captivity, in the outlines of the river gods of the Euphrates and Tigris. Between each pair of outer and inner pillars there are large bas-relief sculptured scenes executed in a very confused and tasteless style. The four lower and narrow compartments show the goddess Roma receiving the homage of the East, which is personified by a woman wearing a tiara. Behind her, in a long train of carts and carriages, come the spoils of the various nations conquered by Severus. Above this narrow line of figures which runs round below the four compartments above the side arches, are four larger bas-reliefs representing the sieges and victories of Severus in Parthia, Adiabene, and Arabia. On the side towards the Forum is represented on the left hand the raising of the Parthian siege of Nisibis in northern Mesopotamia by Severus after he had crushed his rivals Æmilianus and Pescennius Niger in Pontus and Syria. The taking of the town of Carræ west of Nisibis, and the march of the Roman army thence against the Adiabenians are also here portrayed. The compartment, on the right hand, looking from the Forum, contains a bas-relief representation of the surrender of Abgarus, king of Osroene,[60] and the siege of the town of Hatra on the Tigris. [Illustration: Arch of Severus.] On the other side towards the Capitol and so-called Tabularium, the second campaign of Severus in the East is portrayed. On the right hand the flight of the Parthians from Babylon, the entry of the Romans into that city and the second siege of Hatra are represented. On the left is the wresting of the towns of Seleucia and Ctesiphon from the Parthians, the flight of their king Artobanus and the surrender of the Arabians who had joined the Parthian side.[61]