As the walls arose, the viceroy of Syria presided, Suleiman's imperial architect Sinan probably inspected the work on his way home from Mecca: thousands of workers laboured, new stones were quarried, old stones purloined from ruined churches and Herodian palaces, and the ramparts and gates carefully fused with the Herodian and Umayyad walls around the Temple Mount.
Source: wiktionary