Gachsaran is one of the most extreme sections of Kohkiluyeh Va Boyer Ahmad province. This section was separated in 1959 from the township of Behbahan and came under the township of Kohkiluyeh and recently has been turned into a township. The petroleum region of Gachsaran is located in tropical part which has two kinds of dry and temperate weather.
As a result of its oil fields it is one of the famous centers of petroleum exploitation and exploration, thus very important. Dogonbadan is the center of this township.
This city was named Gonbade Malghan or Gonbade Maljan in the past and now Dogonbadan and Gachsaran. There were two domes, one to the west and one to the east of the city, so the city was called Do gonbadan "between two domes". The city was rebuilt by British staff of the Darcy oil company about 1927.