This Arch is the only remains of the first overpass in classical antiquity.
King Herod, who built the Jewish Temple in Jerusalem at about 20 BC also built a large interchange at the meeting point of the Western and Southern walls. In practice, the walls served as retaining walls that supported the large plaza he built on Mount Moriah which in turn served as a foundation for building the Temple on it. The interchange enabled large numbers of people to climb the stairs from the Tyropheon Valley’s ancient streets to the Royal Stoa (Portico) complex which was located at the elevation of the Temple Mount.
After the Great Jewish Revolt during 70 AD when the Romans destroyed the Temple and the interchange, the ancient shops located under the stairs collapsed. Only the remains of an arch and part of the overpass protrude from the Western Wall. Still visible today, these surviving portions of the Arch at the southern part of the Western Wall was identified by and named after the Biblical scholar Edward Robinson in 1938. Based on archeological findings at the foot of the Western Wall, researchers reconstructed a model of how it would have appeared before the Temple destruction – shown in the picture below.