Peshawar is the sixth most populous city in Pakistan, with a population of over 2.3 million. It is situated in the north-west of the country, close to the International border with Afghanistan. It is the capital of the province of Khyber Pakhtunkhwa, where it is the largest city. Peshawar is primarily populated by Pashtuns, who comprise the second-largest ethnic group in the country. Situated in the Valley of Peshawar, a broad area situated east of the historic Khyber Pass, Peshawar's recorded history dates back to at least 539 BCE, making it one of the oldest cities in South Asia. Peshawar is among the oldest continuously inhabited cities of the country.