Pool of Siloam - Lower Pool

Ancient records report that during the Second Temple period, there was a lower pool. In the Autumn of 2004, Ir David Foundation workers, excavating for a sewer near the present-day pool, uncovered stone steps, and Ronny Reich and Eli Shukron (prominent archaeologists) were called in; it became obvious to them that these steps were likely to have been part of the Second Temple period pool. Excavations commenced and confirmed the initial supposition; the find was formally announced on August 9, 2005 and received substantial international media attention. The pool is less than 70 yards from the edge of the Byzantine reconstruction of a pool previously thought to be the Siloam Pool. This small pool collected some of the water as it emptied there at the southern end of Hezekiah's tunnel. The water continued on through a channel into the recently discovered Pool of Siloam. The source of the water is from the Gihon Spring located at the northern end of Hezekiah's tunnel on the eastern side of the City of David. An ancient pool (Upper Pool) existed near the Gihon Spring but was no longer used after King Hezekiah redirected the waters to the western side of the city.

The lower pool is not perfectly rectangular, but a soft trapezoid. There are three sets of five steps, two leading to a platform, before the bottom is reached, and it has been suggested that the steps were designed to accommodate various water levels. The pool is stone lined, but underneath there is evidence of an earlier version which was merely plastered (to help it retain water). Coins found within this plaster date from the time of Alexander Jannaeus (104–76 BC), while a separate collection of coins, dating from the time of the Great Revolt (AD 66–70), were also found.

How much of the pool and its surrounding structures were a result of monumental construction by Herod the Great is not yet understood (as of September 2006); nor is the relationship of this pool to the earlier one (i.e., why it was built when the earlier pool already existed). A portion of this pool remains unexcavated, as the land above it is owned by a nearby Greek Orthodox church and is occupied by an orchard known as the King's Garden (compare Nehemiah 3:15).

As a fresh water reservoir, it would have been a major gathering place for ancient Jews making religious pilgrimages to the city. The Gospel of John suggests that it was probably used as a mikvah (ritual bath), although mikvahs are usually much smaller in size; if the pool were a mikvah, it would be the largest ever found, by a substantial margin. Yoel Elitzur has proposed that the pool was used for swimming rather than ritual immersion. It is thought that the current structure was originally the Shrine of the Four Nymphs (Tetranymphon), a nymphaeum built by Hadrian during the construction of Aelia Capitolina in 135, and mentioned in Byzantine works such as the 7th century Chronicon Paschale; other nymphaeum built by Hadrian, such as that at Sagalassos, are very similar.