The Indus-Sarasvatī Civilisation (c. 2600-1900 BCE) was one of the world's oldest civilisations, remarkable for its urban planning and civic infrastructure.

Cities like Harappa, Mohenjo-daro, Dholavira and Rakhigarhi featured wide streets oriented to cardinal directions, fortifications dividing upper and lower towns, and sophisticated drainage systems running below streets.

Water management was exceptional—Mohenjo-daro had about 700 brick wells, while Dholavira had at least six large reservoirs connected by underground drains.

The Harappans developed productive agriculture, growing wheat, barley, millets, rice, pulses, vegetables, and cotton—the first in Eurasia to cultivate it.

Their crafts included sophisticated bead-making using carnelian, shell bangle production, bronze metallurgy, and ivory work.

Maritime trade extended to regions like Oman, with Lothal possessing a massive dockyard.

Thousands of seals with undeciphered writing reflect administrative sophistication.

Despite eventual decline around 1900 BCE due to climatic changes and the Sarasvatī River drying up, Harappan cultural and technological achievements influenced later Indian civilisation.