The Indus Valley civilization flourished around 2,500 B.C. in the western part of South Asia. Today it comprises the regions of present Pakistan and western India. It is often referred to as Harappan Culture or Civilization because Harappa was the first city discovered of the civilization. The Indus Valley is the largest of the four urban civilizations of the ancient world Egypt, Mesopotamia, India and China. It was not discovered until the 1920's. The script used by the Indus Valley people has yet not been deciphered. The Harappans used the standard bricks and weights for a thousand miles.

Mohenjo-daro is known for remarkable construction of the buildings. It layout of the city was planned and based on a grid of streets. The buildings were constructed of baked mud bricks, sun dried bricks and burned wood. At the pek of its development, the city of Mohenjo-daro probably had around 35,000-40,000 residents.

Mohenjo-daro had an highly developed drainage system, a variety of buildings almost two stories high and an elaborate bath area. Among the most striking buildings in Mohenjodaro are the Great Bath measuring 39x23x8 feet. The Great Bath probably had a ritual significance. The bath area was well-built and had a layer of natural tar to prevent it from seeping. It was agricultural city and also had a large well, granary and a central marketplace. Mohenjo-daro even had a building with an underground furnace possibly for heated bathing.

There seem to have been a flourishing trade and commerce, which seems to have laid the foundations of a comfortable urban life. The available evidence suggests that Mohenjo-daro has trade relations with Saurashtra and Deccan. Silver and lapis lazuli were imported from Persia and Afghanistan. Jadeite was brought from Tibet and Central Asia. A few seals found in Mesopotamia suggest that businessmen from Indus valley also resided there at one point of time.

The impressive figurines excavated in Mohenjodaro include a dancing girl in bronze and a priest like man draped with a shawl. the figure of the dancing girl is naked but adorns a single necklace. The Dancing girl is the most famous find of the Indus Valley Civilization and tells us about the development of the civilization in the science of metallurgy.

The city was successively destroyed and rebuilt at least seven times. Each time, the new cities were built directly on top of the old ones. The cause of the destruction of the city is considered excessive floding by the river Indus.