Mohenjo-Daro, archaeological site of the Indus Valley, or Harappān, civilization (2500?-1700 bc), south of Lārkāna, Pakistan. Excavated in the 1920s by the British archaeologist Sir John Marshall (1876-1958), Mohenjo-Daro covers more than 80 hectares (200 acres) and consists of two mounds separated by an unoccupied area. A major city and commercial center during the Bronze Age, it is the largest Indus Valley settlement. The small western mound, or “citadel,” has several public buildings, which may have been surrounded by a wall. Early excavators took these buildings for a granary, assembly hall, college, and public bath, but later studies have cast doubt on that conclusion. The larger eastern mound consists of large blocks of brick buildings, separated by streets and housing the inhabitants' residences and workshops. Both mounds yielded an abundance of Harappān artifacts.