Discovered in the 1920s, it was thought to have been confined to the Indus valley. However, subsequent excavations established that, this civilization was not restricted to the Indus valley but spread to a wide area in northwestern and western India.

The recent excavation and Satellite mapping shows that this areas were more prominent on the banks of erstwhile Sarasvati river, which later on dried and paved way for Thar Desert. Since the first excavation was on the site known as Harappa, it is also known as Harappan civilization.

Some of the important cities were Mohenjo-daro, Harappa, Chandudaro, Kalibangan, Banavali, Lothal and Rupad.

The main characteristic feature of this civilization was its urbanization and they were far more advanced than their counterparts in Egypt, Mesopotamia or anywhere else in Western Asia. The cities show evidence of an advanced sense of planning and organization. Each city was divided into the citadel area, where the essential institutions of civic and religious life were located, and the residential area where urban population lived.

The streets ran straight and at right angles to each other following the grid system and were unique to this civilization. The roads were very wide and the houses were built of burnt bricks and lined both sides of the street. The houses were of varying sizes and had a remarkable drainage system of ceramic drain pipes, covered sewers and valuated subterranean conduits.

As in most other contemporary civilizations, agriculture was the backbone of the Indus economy. The people made extensive use of the wooden plough. Barley and wheat were the main food crops. Perhaps the most remarkable achievement was the cultivation of cotton. The people ate, besides cereals, vegetables and fruits, fish, fowl, mutton, beef and pork. There is also evidence of the domestication of cats, dogs, goats, sheep and perhaps, the elephant.

The Indus people made extensive use of bronze and copper. There is a debate on their knowledge of iron. The people were very artistic. Evidence can be found in the pottery, stone sculpture and seal making. The pottery was made up of well-fired clay, with painting in black pigment. People worshipped natural forces like the tree, humped bull and Mother Goddess. Even amulets and charms were used by the people to ward off evil spirits.

They had commercial links with Afghanistan, Persia, Egypt, Mesopotamia and the Samaritans. Trade was in the form of 'Barter '. There was a cleverly organized system of weights and measures. The script during this period was pictographic. The writing was bonstrophedon or from right to left and from left to right in alternate lines.

They knew mining, metalworking and the art of constructing well-planned building, some of which were higher than two stories. They used gypsum cement that was used to join stones and even metals. They knew about long lasting paints and dyes. The great bath of Mohenjo-daro worked by an ingenious hydraulic system.

There is a striking contrast between the rest of the civilization and the Indus valley in the way it was managed. In other areas, much money and thought were lavished on the building of magnificent Temples of Gods, Palaces and Tombs of kings. The common people seemingly had to content themselves with insignificant dwellings of mud. In the Indus, valley the picture is reversed. The finest structures were erected for the convenience of the citizens.

During the period of late 2000 BC, the main river Sarasvati, on which this civilization flourished, slowly started to dry. Decreasing fertility and the expansion of the Thar desert, finally forced this civilization to move towards north and north-east of Indian sub-continent and the beautiful cities were abandoned and left for ruins.