The arena, which probably succeeded an earlier wooden structure is slightly larger and later than the one at Nimes and by the same architect. It measures 446 x 351 ft. and could seat some 26,000 spectators. The seating is supported on two rows of sixty arches, the lower framed with Doric half columns and the upper with Corintian. The attic storey has disappeared as have most of the internal stairways and galleries, but the remaining galleries are roofed in Greek style with flat stone slabs.