Khorramabad, Lorestan

Falak ol Aflak Castle is a castle situated on the top of a large hill with the same name within the city of Khorramabad, the regional capital of Lorestan province, Iran. This gigantic structure was built during the Sassanid era (226–651). The Khoramabad River runs past the eastern and south-western side of the Falak ol Aflak hill providing the fortress with an element of natural protection.