The Sultan's Pool was built by building a dam across the Valley of Hinnom, which stopped the drainage of the valley south towards the Kidron Valley and created a water reservoir. In place of the dam, an ancient bridge had previously passed, over which the lower aqueduct that carried water from Solomon's Pools near Bethlehem to Jerusalem and the Temple Mount passed. A covered and plastered rock-hewn canal from the Roman period was discovered throughout the pool; it is likely from the time of Herod. Some scholars identify it with the Snake Pool mentioned by Josephus.

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