The Indus Valley

In 1856, British railway engineers building a line through the Punjab needed ballast, crushed rock to lay beneath the tracks. Local workers pointed them toward a nearby mound of ancient bricks. The engineers used thousands of them, unknowingly grinding up the remains of a city 4,600 years old.

Sixty years passed before anyone understood what had been found. In 1921, archaeologist Daya Ram Sahni began systematic excavations at the site, called One of the two major urban centers of the Indus Valley Civilization, located in present-day Punjab, Pakistan. Discovered in the 1820s but not excavated until 1921, Harappa gave the civilization its alternative name: the Harappan Civilization.. The following year, R. D. Banerji started digging at another mound 400 miles south: The largest known city of the Indus Valley Civilization, located in present-day Sindh, Pakistan. The name means 'Mound of the Dead' in Sindhi. At its peak around 2500 BCE, it may have housed 40,000 to 50,000 people., "the Mound of the Dead."

What came out of the ground upended assumptions. These were not primitive settlements. They were meticulously planned cities, among the largest in the ancient world, belonging to a civilization that modern scholarship had known nothing about. The Indus Valley Civilization (also called the Harappan Civilization) had been erased from human memory entirely.