From the beginning of the 4th millennium BC, the individuality of the early village cultures began to be replaced by a more homogenous style of existence. By the middle of the 3rd millennium, a uniform culture had developed at settlements spread across nearly 500,000 square miles, including parts of Punjab, Uttar Prades
h, Gujarat, Baluchistan, Sind and the Makran coast.This earliest known civilisation in India, the starting point in its history, dates back to about 3000 BC. Discovered in the 1920s, it was thought to have been confined to the valley of the river Indus, hence the name given to it was Indus Valley civilisation. This civilisation was a highly developed urban one and two of its towns, Mohenjodaro and Harappa, represent the high watermark of the settlements. Subsequent archaeological excavations established that the contours of this civilisation were not restricted to the Indus valley but spread to a wide area in northwestern and western India. Thus this civilisation is now better known as the Harappan civilisation. Mohenjodaro and Harappa are now in Pakistan and the principal sites in India include Ropar in Punjab, Lothal in Gujarat and Kalibangan in Rajasthan.
