How old are ancient Indus cities? Excavations at Harappa show activity going back to approximately 3500 BCE, as do excavations at Mohenjo-daro. Neither site has been fully excavated, however. Attempts to go deep at Mohenjo-daro failed. As Sir Mortimer Wheeler wrote, "The lower level of excavations at Mohenjo-daro have never been reached by excavation due to difficulties of a high water-table. The two photographs illustrate an attempt made with pumps in 1950 to reach the lower levels and the subsequent flooding which happened overnight." (Civilizations of the Indus Valley and Beyond, p. 73). Recent excavations at Rakigarhi have Professor Vasante Shinde reporting layers from 5500 BCE which would be the earliest known levels at an Indus civilization city. The earliest known towns like Mehrgarh in Balochistan go back to about 7000 BCE, although there is no known Indus connection.
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