Herod built three towers on the north side of his palace, which sat along the inside of the west wall of the city of Jerusalem.
The towers were called:
-Phasael, after Herod’s brother; this tower was housed a luxury apartment
-Hippicus, after Herod’s friend; this tower was for water storage
-Mariamne, after Herod’s favorite wife; this tower was the location of another extravagant luxury apartment
The base of Phasael Tower sits in a dry moat inside the Jaffa Gate by the Citadel. This used to be the northwest corner of Herod’s city of Jerusalem.
Three portions of Herod’s Phasael tower can be seen in the photo above. The lower portion is built on an incline like a glacis (an artificial slope built against a fortification for military defense). The middle portion is part of Herod’s original tower of Phasael built around 20 BC, along with the base. The upper portion was built by Suleiman the Magnificent in 1537.