Masada is a mountain-top fortress complex in the Judaean Desert, overlooking the western shore of the Dead Sea in southeastern Israel. The fort, built in the first century BC, was constructed atop a natural plateau rising over 400 m (1,300 ft) above the surrounding terrain, 20 km (12 mi) east of modern Arad.
The most significant remains at the site date to the reign of Herod the Great, King of Judaea c. 37–4 BC, who transformed Masada into a fortified desert refuge early in his rule. He enclosed the summit with a casemate wall and towers, and constructed storerooms, an advanced water system, and bathhouses, along with two elaborate palaces: one on the western side and another built across three terraces on the northern cliff.