Karaj is a city in the Central District of Karaj County, Alborz province, Iran, serving as capital of the province, the county, and the district. Earliest evidence of inhabitation in Karaj can be dated to the Bronze Age at Tepe Khurvin. The city was developed under the rule of the Safavid and Qajar Empire and is home to historical buildings and memorials from those eras. This city has a unique climate due to access to natural resources such as many trees, rivers, and green plains. After Tehran, Karaj is the largest immigrant-friendly city in Iran, so it has been nicknamed "Little Iran."