Dera Ismail Khan, abbreviated as D.I. Khan, is a city and headquarters of Dera Ismail Khan District, located in Khyber Pakhtunkhwa, Pakistan. It is the 10th largest city of Pakistan and third or fourth largest in the province of Khyber Pakhtunkhwa by population. Dera Ismail Khan is situated on the west bank of the Indus River, at its junction with the Gomal River.