[custom_adv] Karaj is the capital of Alborz Province and effectively a suburb. Although the county hosts a population around 1.97 million, as recorded in the 2016 census, most of the 1,419 sqkm county is rugged mountain, the urban area is the fourth-largest, after Capital. [custom_adv] Eshtehard County and Fardis County were split off from Karaj county since the previous census. The earliest records of Karaj date back to 30th century BC. [custom_adv] The city was developed under the rule of the Safavid and Qajar dynasties, and is home to historical buildings and memorials from those eras. [custom_adv] Until the second half of the 20th century, it used to be known mainly as a summer resort. Today, it is a major industrial city, with factories producing sugar, textiles, wire, and alcohol. [custom_adv] Karaj has been hosting communities since 3000 years BC. The Khurvin region of Karaj has been inhabited since the Bronze Age, and the Kelāk region on the left bank of Karaj River since the Iron Age. [custom_adv] The stone built Taxt e Rostam, located on a mount in the west of Šahriār County, was built in the Parthian era as a Zoroastrian fire temple. [custom_adv] Until the late 20th century, the city was mainly crossed into by a stone bridge built in the Safavid era. The stone built Šāh-Abbāsi Caravansary, located at the southeast of Towhid Square, was built in the same era, under the rule of Šāh Esmāil.
