Among the settlements were the major urban centres of Harappa, Mohenjo-daro (UNESCO World Heritage Site), Dholavira, Ganeriwala in Cholistan and Rakhigarhi, Rakhigarhi in Haryana, India, being the largest Indus Valley Civilization site with 350-hectare (3.5 km 2) area.t its peak, the Indus Civilization may have had a population of more than 5 million. Inhabitants of the ancient Indus river valley developed new techniques in handicraft (carnelian products, seal carving) and metallurgy (copper, bronze, lead, and tin).