The other wall is behind, perpendicular, forming the corner.

Outside the city, two walls of the "Temple of Janus" (2nd century AD) stand 24 m high. It was a temple of Romano-Celtic type, having a square central cella of petit appareil (a facing of courses of small squared blocks of stone) with three windows on each side and a surrounding ambulatory. Aerial photography in 1976 detected adjacent buildings of the rural sanctuary, including a theatre.