Much of the Mount's early history is synonymous with events pertaining to the Temple itself. After the destruction of Solomon's Temple by Nebuchadnezzar II, construction of the Second Temple began under Cyrus in around 538 BCE, and was completed in 516 BCE. Evidence of a Hasmonean expansion of the Temple Mount has been recovered by archaeologist Leen Ritmeyer. Around 19 BCE, Herod the Great further expanded the Mount and rebuilt the temple. The ambitious project, which involved the employment of 10,000 workers, more than doubled the size of the Temple Mount to approximately . Herod leveled the area by cutting away rock on the northwest side and raising the sloping ground to the south. He achieved this by constructing huge buttress walls and vaults, and filling the necessary sections with earth and rubble. A basilica, called by Josephus the Royal Stoa, was constructed on the southern end of the expanded platform, which provided a focus for the city's commercial and legal transactions, and which was provided with separate access to the city below via the Robinson's Arch overpass. In addition to restoration of the Temple, its courtyards and porticoes, Herod also built the Antonia Fortress, abutting the northwestern corner of the Temple Mount, and a rainwater reservoir, Birket Israel, in the northeast. As a result of the First Jewish-Roman War, the fortress was destroyed in 70 CE by Titus, the army commander and son of Roman emperor Vespasian.