Megasthenes

Born in Ionia (today's Turkey), Megasthenes wrote the earliest account of India. There, he met the ruler of the Mauryan Empire Chandragubta, and travelled through today's Pakistan, the Indus valley and Afghanistan reaching Pataliputra on the Ganges river.
In doing this, he was probably the first European to see the holy river. Megasthenes wrote about his journeys, but only little has survived to posterity. In his works he mentioned, apart from the above, the Himalayas, Tibet and Sri Lanka. He also wrote about the Indian nature, religious practices and the caste system.