The earliest known civilization of the Indian subcontinent was located in Mehrgarh, which is now part of modern-day Pakistan. Mehrgarh is an archaeological site located in the Kachi Plain of Balochistan, Pakistan. It is considered one of the earliest sites of settled agriculture in South Asia and one of the most important archaeological discoveries of the 20th century.

1. Discovery and Excavation:
Mehrgarh was first discovered in 1974 by French archaeologist Jean-François Jarrige. Excavations at the site have been carried out since then by a team of archaeologists from France and Pakistan. The excavations have revealed a wealth of information about the early development of human civilization in the Indian subcontinent.

2. Age and Chronology:
The site of Mehrgarh has been occupied for over 8,000 years, with evidence of human habitation dating back to around 7000 BCE. The site was inhabited during the Neolithic period and the early Bronze Age, making it one of the oldest known settlements in the region.

3. Agricultural Practices:
One of the key findings at Mehrgarh is evidence of early agricultural practices. The inhabitants of Mehrgarh were among the first in the region to domesticate plants and animals. They cultivated crops such as wheat, barley, and lentils, and also raised domesticated animals like cattle, sheep, and goats. This shift from a nomadic lifestyle to settled agriculture marked a significant milestone in human history.

4. Social Organization:
The archaeological findings at Mehrgarh also provide insights into the social organization of the early civilization. The site shows evidence of a hierarchical society, with different levels of wealth and social status. The presence of elaborate burial practices and the discovery of pottery and other artifacts suggest a sophisticated culture.

5. Trade and Exchange:
Mehrgarh was strategically located along ancient trade routes, which allowed for the exchange of goods and ideas with neighboring regions. Archaeological excavations have uncovered artifacts such as beads made of semi-precious stones and shells, indicating long-distance trade.

6. Influence on Later Civilizations:
The civilization at Mehrgarh is believed to have had a significant influence on the development of later civilizations in the Indian subcontinent, such as the Indus Valley Civilization. The agricultural practices, social organization, and trade networks established at Mehrgarh laid the foundation for the growth of complex urban societies in the region.

In conclusion, the earliest known civilization of the Indian subcontinent was located in Mehrgarh. The site's significance lies in its early agricultural practices, social organization, and influence on subsequent civilizations. The archaeological findings at Mehrgarh have provided valuable insights into the origins and development of human civilization in the Indian subcontinent.