The Kidron Valley
This is the Kidron Valley below the Golden Gate (right of center along the wall) with the Mount of Olives behind . In 2000 the ground near the Golden Gate collapsed revealing a gate below the modern one. The hole was filled as this area is a Moslem graveyard. The southwestern portion of this wall was close to first century Herodian (Second Temple era) foundations of the outer wall of Jerusalem. Jesus may have exited a gate facing east towards the spot the photo was taken from.
View of the city wall from the Mount of Olives