Rawalpindi (راولپنڈی, Rawalpindi) is a city in the Pothohar region of Pakistan in Punjab province near Pakistan's capital city of Islamabad. Rawalpindi is the fourth largest city in Pakistan after Karachi and Lahore. In the 1950s, Rawalpindi was smaller than Hyderabad and Multan, but the city's economy received a boost during the building of Islamabad (1959–1969), during which time Rawalpindi served as the national capital and its population increased from 180,000 to over 2.1 million. Rawalpindi is located in the Punjab province, 275 km (171 miles) to the north-west of Lahore. It is the administrative seat of the Rawalpindi District. The total area of the city is approximately 154 square kilometres (59 sq mi). Rawalpindi is the military headquarters of the Pakistani Armed Forces.