Warren's Gate, first described by the nineteenth century surveyor Charles Warren, is an ancient entrance into the Temple platform in Jerusalem which lies about 150 feet (46 m) into the Western Wall Tunnel. In the Second Temple period, the gate led to a tunnel and staircase onto the Haram al-Sharif. After the Rashidun Caliphate conquest of Jerusalem from the Byzantines, Jews were allowed to pray inside the tunnel. The synagogue was destroyed in the First Crusade in the Siege of Jerusalem in 1099. The tunnel then became a water cistern, thus its name Cistern 30.
The arch in the wall to the right is the closed gate discovered by Charles Warren. The area is surrounded by a vaulted 18-foot (5.5 m) tunnel, probably built by the Crusaders. Rabbi Yehuda Getz, the late official Rabbi of the Western Wall, believed that the Gate represented the point west of the Wall closest to the Holy of Holies. He therefore established a small synagogue at the location.