Khalkhal (Persian: خلخال, also Romanized as Khalkhāl; formerly, Herowabad (Persian: هرو آباد) also Romanized as Herowābād, Harowabad, Herauabad, Heroābād, and Hirābād; also formerly, Herow (Persian: هِرُو), also Romanized as Harau and Herau) is a city in and the capital of Khalkhal County, in Ardabil Province, Iran. At the 2006 census, its population was 38,521, in 9,619 families.