Indus Valley civilization was one of the world's first great civilizations. The civilization began to flourish about 4,500 years ago and was centred in the vast river plains of what are now Pakistan and northwestern India. This civilization is sometimes called the Harappan civilization. It is named after the Pakistani town of Harappa, where archaeologists first discovered evidence of the culture.
The Indus civilization developed out of farming and herding communities that carried on trade with each other. About 2500 B.C., the communities became more unified culturally, and in some places people began laying out carefully planned cities. In time, the Indus civilization grew to cover most of present-day Pakistan and parts of what are now Afghanistan and northern India. The heart of the civilization was the vast flood plain of the Indus and Hakra rivers. The Hakra River (also known as the Ghaggar River or Sarasvati River) is now dried up.
It once flowed east of--and parallel to--the Indus River, in what are now India and Pakistan. The civilization developed a standardized system of weights and measures and a system of writing that used pictographs (simple drawings representing words).
In the early 1800's, British scholars learned that people had found ancient artefacts buried in huge earthen mounds in the region. But it was not until the 1920's that archaeologists began excavating these sites and realized that they contained the remains of cities from a previously unknown civilization. Hundreds of Indus sites have been found.
The Indus people planned their cities carefully. They built many of their buildings on mud-brick platforms that protected the buildings from seasonal floods. Houses were made of baked or sun-dried brick. Many houses had two storeys. Most homes had a bathing area that was supplied with water from a nearby public well or from a...