Karaj is the fourth largest city in Iran, being in close proximity of the capital Tehran. It is in the Central District of Karaj County, Alborz province, Iran, and serves as capital of the county. Although the county hosts a population around 1.97 million, as recorded in the 2016 census, most of the 1,419 km2 (548 sq mi) county is rugged mountain. The urban area is the fourth-largest in Iran, after Tehran, Mashhad, and Isfahan. Eshtehard County and Fardis County were split off from Karaj County since the previous census.
