India's earliest urban (Bronze Age) civilisation, also called the Indus Valley Civilisation, that flourished mature from about 2600 to 1900 BCE across the Indus and Saraswati (Ghaggar-Hakra) basins.
- First discovered through excavations at Harappa (1921, Daya Ram Sahni) and Mohenjodaro (1922, R. D. Banerji), under the Archaeological Survey of India led by John Marshall.
- Known for planned cities, grid-pattern streets, a sophisticated drainage system, the Great Bath at Mohenjodaro, and a standardised system of weights and measures.
- Major sites: Harappa and Mohenjodaro (Pakistan), and Lothal (dockyard), Dholavira (water harvesting), Kalibangan (ploughed field), Rakhigarhi, and Banawali in India.
- Used a still-undeciphered script (written right to left, boustrophedon), and traded with Mesopotamia (Sumer) via the port of Lothal.
- Decline (around 1900 BCE) is debated: climate change and a drying Saraswati, floods, or shifting rivers, not a single Aryan invasion.
Site-to-feature matching (Lothal-dockyard, Kalibangan-ploughed field, Dholavira-water systems) and discovery dates are high-frequency ancient-history facts.
Mohenjodaro and Harappa are in present-day Pakistan, while Lothal, Dholavira, Kalibangan, and Rakhigarhi are in India; the script remains undeciphered.
Bronze Age urban civilisation (mature 2600 to 1900 BCE) of planned cities, drainage, and an undeciphered script.