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When Cunningham, the first Director-General of the ASI, began archaeological excavations in the mid-nineteenth century, archaeologists preferred to use the written word (texts and inscriptions) as a guide to investigations. In fact, Cunningham’s main interest was in the archaeology of the Early Historic (c. sixth century BCE-fourth century CE) and later periods. He used the accounts left by Chinese Buddhist pilgrims who had visited the subcontinent between the fourth and seventh centuries CE to locate early settlements. Cunningham also collected, documented and translated inscriptions found during his surveys. When he excavated sites he tended to recover artefacts that he thought had cultural value. A site like Harappa, which was not part of the itinerary of the Chinese pilgrims and was not known as an Early Historic city, did not fit very neatly within his framework of investigation. So, although Harappan artefacts were found fairly often during the nineteenth century and some of these reached Cunningham, he did not realise how old these were.

Why did Harappan artifacts found during the nineteenth century that reached Cunningham not reveal their true age?

Limited knowledge of the Harappan civilization