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c. 2600 BCEReputable source · 2 sourcesWell documented

The Indus Valley Civilization Builds Its First Cities

Harappa and Mohenjo-daro rise as planned cities on a scale unmatched anywhere else in the ancient world

On the timeline · around c. 2600 BCE · Mehrgarh and the Indus Valley CivilizationMehrgarh and the Indus Valley CivilizationThe Vedic PeriodThe Indus Valley Civilization Builds Its First Cities4,500 BCE4,000 BCE3,500 BCE3,000 BCE2,500 BCE2,000 BCE1,500 BCE

Quick facts

Key cities
Harappa and Mohenjo-daro, in modern Pakistan
Estimated city population
40,000-50,000 each
Territory
Over 900 miles (1,500 km) along the Indus River
Discovery
Recognized as a civilization by John Marshall, ASI, from 1904

What happened

By around 2600 BCE, villages along the Indus and its tributaries had grown into the Indus Valley Civilization's two best-known cities, Harappa and Mohenjo-daro, each thought to have held between 40,000 and 50,000 people at a time when most ancient cities held closer to 10,000. Unlike cities that grew organically from smaller settlements, Harappan cities were laid out on a grid before they were built, with a raised citadel mound separated from a lower residential town. British archaeologist John Marshall, appointed head of the Archaeological Survey of India in 1904, visited Harappa and recognized it as evidence of a civilization no one had previously identified; formal excavation at Mohenjo-daro began in the 1924 to 1925 season, confirming the two sites belonged to the same culture. At its height the civilization's territory stretched more than 900 miles along the Indus and its population is estimated at upward of five million, with sites found as far as the borders of Nepal and Afghanistan.

Why it matters

The Indus Valley Civilization is one of the first urban societies anywhere, alongside Mesopotamia and Egypt, and the only one of the three built on a scale of deliberate city planning rather than gradual accretion. Its cities set the template, citadel and lower town, gridded streets, uniform brick sizes, that every later Indus settlement across a subcontinent-sized territory would repeat.

How we know

The dating and population estimates come from a century of excavation beginning with Marshall's 1920s campaigns, cross-checked against the uniform brick ratios and city layouts found at dozens of Indus sites across Pakistan and northwest India.

Sources

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Part of a timelineAncient India29 events · From the granaries of Mehrgarh to the astronomers of the Gupta court, the long record of the Indian subcontinent's first cities, philosophies, and empiresView all →