This period was the beginning of a migration of people from small villages into Khorramabad. The increase in population led to the expansion of the city and the creation of new districts. Pahlavi dynasty Khorramabad Municipality was formed in 1913 and the first city council, consisting of seven members, was formed in 1916. Geography Location The city is located inside a valley and has been surrounded by mountains. The two main mountains around the city are EspiKouh (SefidKouh) and Makhmalkouh. The city is rich of underground resources and five main springs passes through it. It has one river called as Gelal or KhorramRud (new name). Climate KhorramAbad has mild and semi-humid Mediterranean climate with high amount of rainfall during spring and winter. It is the sixth cities in Iran having high level of annual rainfall. Khorramabad has what is classed under the Köppen climate classification as a Hot-summer Mediterranean climate (Csa) climate. Its elevation is 1147.8 above sea level. Average annual precipitation is 511.06 and its average annual temperature is 17.21 Celsius. Main sights ShapurKhast Castle ShapurKhast Castle, sometimes referred to as Dež-e Shāpūr-Khwāst, Falak-ol-Aflak Castle, and known in ancient times as Dezbaz as well as Shapur-Khast, is one of the most impressive castles in Iran. It is situated on the top of a large hill with the same name within the city of Khorramabad, the regional capital of Lorestan province. The Khorramabad River runs past the eastern and south-western side of the ShapurKhast hill providing the fortress with an element of natural protection. Today, the western and northern sides of the hill are bordered by the residential districts of Khorramabad. This gigantic structure was built during the Sassanid era (226–651). It has been known by a number of names since it was built over 1800 years ago. Recorded names have referred to it as Shapur-Khast fortress, Dezbaz, Khorramabad castle, and ultimately the Falak ol-Aflak Castle. The foundations of the actual castle measure approximately 300 meters by 400 meters. The height of the entire structure, including the hill, reaches up to 40 meters above the surrounding area. This space is divided into four large halls, and their associated rooms and corridors. The rooms all surround two courtyards with the following measurements: the first courtyard measures 31×22.50 meters and the second 29x21 meters. When originally built the castle used to have 12 towers, but only 8 remain standing today. The building's