Darreh Shahr or Dar-i Shahr (Persian: دره شهر; also Romanized as Darreh-ye Shahr) is a city in and the capital of Darreh Shahr County, Ilam Province, Iran. At the 2006 census, its population was 18,214, in 3,851 families. The ruined ancient city of Darreh Shahr Ancient City is located in the southern part of Darreh Shahr, and has been extensively excavated by archaeologists. The Seymarah River flows to the north of the city. The city has a lot of potentials in agriculture, rich water supplies, green fields and dense forests.