Western Wall Tunnel

The Western Wall Tunnel (Hebrew: מנהרת הכותל‎‎, translit.: Minheret Hakotel) is an underground tunnel exposing the full length of the Western Wall. The tunnel is adjacent to the Western Wall and is located under buildings of the Old City of Jerusalem. While the open-air portion of the Western Wall is approximately 60 metres (200 ft) long, the majority of its original length is hidden underground. The tunnel allows access to an additional 485 metres (1,591 ft) of the wall.

In 19 BCE, King Herod undertook a project to double the area of the Temple Mount in Jerusalem by incorporating part of the hill on the Northwest. In order to do so, four retaining walls were constructed, and the Temple Mount was expanded on top of them. These retaining walls remained standing, along with the platform itself, after the Temple was destroyed by the Romans in 70 CE.

Since then much of the area next to the walls became covered and built upon. Part of the Western Wall remained exposed after the destruction of the Temple. Since it was the closest area to the Temple’s Holy of Holies that remained accessible, it became a place of Jewish prayer for millennia.

British researchers started excavating the Western Wall in the mid 19th century. Charles Wilson began the excavations in 1864 and was followed by Charles Warren in 1867-70. Wilson discovered an arch now named for him, "Wilson's Arch" which was 12.8 metres (42 ft) wide and is above present-day ground level. It is believed that the arch supported a bridge which connected the Temple Mount to the city during the Second Temple Period. Warren dug shafts through Wilson’s Arch which are still visible today.

After the Six Day War, the Ministry of Religious Affairs of Israel began the excavations aimed at exposing the continuation of the Western Wall. The excavations lasted almost twenty years and revealed many previously unknown facts about the history and geography of the Temple Mount. The excavations were difficult to conduct, as the tunnels ran below residential neighborhoods constructed on top of ancient structures from the Second Temple Period. The excavations were conducted with the supervision of scientific and rabbinic experts. This was to ensure both the stability of the structures above and to prevent damaging the historic artifacts. In 1988 the Western Wall Heritage Foundation was formed, it took over the excavation, maintenance and renovations of the Western Wall and Western Wall Plaza.

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