The city of Islamabad, though relatively young, has thousands of years of pre-construction history. Islamabad Capital Territory, located in the Potohar Plateau, is regarded to be one of the earliest sites of human settlement in Asia. Situated at one end of the Indus Valley Civilization, this area was the first habitation of the Aryan community from Central Asia. Islamabad was one of the routes though which the armies from North and North West passed to invade Indian Subcontinent. Many great armies such as those of Alexander the Great, Genghis Khan, Timur and King Abdali have used this route on their way to Indian Subcontinent. Relics and human skulls have been found dating back to 5000 B.C. that show this region was home to Stone Age man who used the banks of Swaan River as their settlement. Modern Islamabad is based on the old settlement known as Saidpur.