Though ancient Indians left innumerable material remains on the earth’s surface, such as the stone temples in South India and the brick monasteries in eastern India, the major part of these remains lies buried in mounds.
Excavations of some mounds have revealed the cities established around 2500 bc in north-western India. Also revealed is the layout of the settlements, the types of pottery used by the people, the form of their houses, the kind of cereals consumed, the type of their tools, implements or weapons, etc.
Material remains excavated and explored are subjected to various kinds of scientific examination. Their dates are fixed according to the radio-carbon method; computers are also now used for the dating process.
Through an examination of plant residues, especially through pollen analysis, the climate and vegetation of a period of the past can be known. Such examination has established that agriculture was practised in Rajasthan and Kashmir around 7000-6000 bc.
The metal art effects obtained help us to know the stages of development of metal technology. Animal bones show whether the animals were domesticated or not, and the uses they were put to.