 It was initially named Korshunikha (), after prospector Shestak Korshunov who had discovered the Iron Mountain in the 17th century.It was granted urban-type settlement status in the 1950s, after a period of growth following the construction of the western section of the Baikal–Amur Mainline, and renamed Zheleznogorsk ("Iron Mountain Town").With the completion of a major ore processing plant, town status was granted in 1965 under the present name, the suffix "Ilimsky" added to differentiate from other towns of the same name.