Best preserved are the rock reliefs of Tiglath-Pileser I and Shalmaneser III that are carved into the wall of the Tigris tunnel. Their production in 852 BC is shown in the relief of the bronze door bands of the Balawat Gates, now in the British Museum.[2] Above the Tunnel there is a natural rock arch that is connected to the tunnel by a stairway created by the Urartians. Above the exit of the Tunnel there are further caves.