Erbil (ĕr´bīl´ –bĬl´) or Irbil (Ĭr´bīl´ –bĬl´), town (1987 pop. 485,968), N Iraq. A commercial, agricultural, and administrative center with a predominantly Kurdish population, it is one of the world's oldest continually settled towns. The ancient Sumerian and Assyrian city of Urbillum (Arbela) was on this site. The oldest section of the city, at the heart of of modern Erbil, is on an artificial mound surmounted by an old Turkish fort. Since 1992 Erbil has been one of the main towns of the so-called Kurdish Autonomous Region.