Falak-ol-Aflak Castle, Twelve Tower Castle, Kakh-e Atabakan, are the different names of Dež-e Shāpūr-Khwāst in Khorramabad. It is called Falak-ol-Aflak which means the sky of all the skies since the Qajar dynasty.

Being situated on the top of the hill, next to the river and on the Golestan spring, Falak-ol-Aflak castle is standing on the axis of Khorramabad. There are some historical monuments near this ancient castle, such as some prehistoric caves, inscriptions, brick minaret, Gabri water mill, Shapuri Bridge (Broken Bridge), and Gerdab-e Sangi (Gerdau Bardineh). This castle is registered on the Iranian National Heritage List.

During the Sassanid era, Shāpūr-Khwāst city was built near Khorramabad, and after its destruction, Khorramabad was constructed near its ruins. Falak-ol-Aflak was the capital of Hasanwayhids, Khorshidi dynasty, Ganjur, and Buyid dynasty from forth to thirteen century SH, and then it was the Treasury of Badr dynasty and also, it became a garrison and prison.