This document discusses different viewpoints among archaeologists about the timeline of the Harappan civilization in India. John Marshall originally dated the important site of Mohenjodaro between 3250-2750 BC, while Mackay thought it was between 2800-2500 BC. Wheeler then dated the broader Harappan civilization between 2500-1500 BC, while Agrawal used carbon dating to more precisely date it between 2300-1700 BC.