Early 19th-century explorers of Jerusalem had many theories for identifying the Millo. Intriguingly, they often associated the Millo with a pool of water, such as the Mamilla Pool, Pool of Hezekiah, or Siloam Pool. The Mamilla Pool, located just west of the wall of the Old City, is particularly interesting, as Murj al-Din, the late 15th-century historian who lived in Jerusalem, notes that local Jews referred to the pool as “Beth Millo.”1 Mamilla and Millo certainly sound similar, and the former likely derives from “waters of Millo” in Hebrew.
It is worth remembering that for most of the last two millennia, key monuments from the time of the biblical kings—David’s palace (the “Tower of David”), David’s tomb, and Mt. Zion itself—were thought to be located on Jerusalem’s western hill, the area now commonly identified with the Old City’s Christian, Armenian, and Jewish Quarters.
With the advent of modern archaeology, however, these traditional identifications proved to be off the mark, as excavation revealed the City of David (the eastern hill) to be the core of the Bronze and Iron Age city, not the western hill. Nevertheless, the long-standing traditions that associated the Millo with prominent pools of Jerusalem still seem to hold water.