The world’s oldest known monumental arch, part of a gateway, has been unearthed by the Leon Levy Expedition to Ashkelon, headed by Harvard professor Lawrence E. Stager. Some older arches have been found in Mesopotamia and Egypt but they are smaller and part of domestic dwellings or subterranean chambers, not in public settings. The Ashkelon arch dates to 1900–1750 B.C. and measures 11.5 feet high and 8 feet wide on the inside. The structure, made of sun-dried bricks, is thought to have been the innermost of three arched gateways through which one entered the city from the north.