the time of the Hasmonean kings, when what Josephus Flavius called "the First Wall" was constructed. Herod's towers Herod, who wrestled the power away from the Hasmonean dynasty, added three massive towers to the fortifications in 37–34 BCE. He built these at the vulnerable northwest corner of the Western Hill, where the Citadel is now located. His purpose was not only to defend the city, but to safeguard his own royal palace located nearby on Mount Zion. Herod named the tallest of the towers, in height, Phasael, in memory of his brother who had committed suicide while in captivity. Another tower was called Mariamne, named for his second wife whom he had executed and buried in a cave to the west of the tower. He named the third tower Hippicus after one of his friends. Of the three towers, only the base of one of them survives until today—either the Phasael or, as argued by archaeologist Hillel Geva who excavated the Citadel, the Hippicus Tower. Of the original tower itself (now called the Tower of David), some sixteen courses of the Herodian stone ashlars are still rising from ground level (partially hidden by a much later built glacis), upon which were added smaller stones in a later period, which added back significantly to the height of the remaining stump of the Herodian tower. During the Jewish war with Rome, Simon bar Giora made the tower his place of residence. Following the destruction of Jerusalem by the Romans in 70 CE, the three towers were preserved as a testimony of the might of the fortifications overcome by the Roman legions, and the site served as barracks for the Roman troops. When the empire adopted Christianity as its favoured religion in the 4th century, a community of monks established itself in the citadel. It was during the Byzantine period that the remaining Herodian tower, and by extension the Citadel as a whole, acquired its alternative name—the Tower of David—after the Byzantines, mistakenly identifying the hill as Mount Zion, presumed it to be David's palace mentioned in . Early Muslims, Crusaders, Ayyubids After the Arab conquest of Jerusalem in 638, the new Muslim rulers refurbished the citadel. This powerful structure withstood the assault of the Crusaders in 1099, and surrendered only when its defenders were guaranteed safe passage out of the city. During the Crusader period, thousands of pilgrims undertook the pilgrimage to