In the Western Wall Tunnels, visitors can also see Warren's Gate. In the Second Temple period, it led from the street that Herod built along the Western Wall to an underground passageway that connected to the Temple Mount Plaza via a flight of stairs.
With the destruction of the Temple, the gate was abandoned. It was only after the Muslim conquest of Jerusalem from the hands of the Byzantines (in the year 638) that Jews were permitted to establish a synagogue located in the gate, known as The Cave, because it was underground. The synagogue was for Jews the closest point to the Holy of Holies. When the Crusaders took the city (in 1099), they annihilated the local Jewish community, destroyed the synagogue, and turned the arch space into a cistern.