In summer 2004 Ronnie Reich and Eli Shukron uncovered the stone steps to a large (50m x 60m, 3 dunam) pool at the southern end of Ir David, the City of David, dated to the end of the Second Temple period and built by King Herod. Further excavations unearthed the north-east corner and northern edge of the pool and a promenade that ascends via steps to a square overlooking the pool and the beginning of a stepped street that runs 800 meters from the bottom of the City of David to the Temple Mount, connecting with the Herodian street below Robinson’s Arch. The stone surface covers an earlier pool from the Hasmonean period.
For Jews, this is the Shiloach Pool, where the ‘living waters’ were used for ritual cleansing in the Temple and the Festival of the Water Libation during Sukkot. For Christians, the Siloam Pool is one of the two places in Jerusalem where Jesus performed miracles (the other is the Bethesda Pool in the Old City), see John 9: “The man called Jesus made mud, smeared it on my eyes and told me, ‘Go to Siloam and wash.’ So I went and washed, and was able to see.” Until this discovery, the Siloam Pool was thought to be the small pool at the end of Hezekiah’s tunnel, part of the Church of Siloam built by the Empress Eudocia between 400 and 450. The round parts of stone columns visible in the pool apparently came from the columns that adorned the promenade of the Herodian pool.
The site of yet another Pool of Siloam which would predate these two is still unknown. That first pool (Shelah Pool, mentioned in Nehemiah 3:15) was constructed in the 8th century BC by Judean King Hezekiah, in anticipation that the Assyrians would lay siege to Jerusalem to hold the waters of the Gihon Spring, brought to it by Hezekiah’s tunnel.
“Now the rest of the acts of Hezekiah, and all his might, and how he made the pool, and the conduit, and brought water into the city, are they not written in the Book of the Chronicles of the Kings of Judah?” (2 Kings 20:20)
Even earlier, in the 18th C BCE (MB II), the inhabitants of Canaanite Jerusalem collected both rainwater and runoff from the City of David hill and the Western hill in a pool at the mouth of the central valley. They also channeled the water of the Gihon Spring to the pool through a conduit (open to the sky), known as the Canaanite Tunnel which runs along the eastern slope of the city.
Illustrations are from the INPA-City of David brochure on the Shiloach Pool