Darreh Shahr Ancient City  Darreh Shahr Ancient City, also known as Madaktu and Seymareh, is the name of a ruined area next to the existing city of Darreh Shahr in southwest Iran, in Ilam Province. The ruins belong to an ancient city of the late Sassanid era (224 – 651 AD) and is believed to be built on remnants of the Elamite capital, Madaktu. Historic texts and also recent findings reveal the fact that the city included about 5,000 houses with some modern aspects like water water distribution system through clay pipes and underground sewers. The city was destroyed and deserted after a huge earthquake around 950 AD. In ancient times, Elamites governed the Lorestan mountains and constructed several strong buildings. Darreh-Shahr was the first Elamite city attacked and destroyed by Assyrians, in addition to the massacre of people. In Seymareh Valley, the remains of Sassanid monuments are still present. Hence Dareh-Shahr might have been a thriving city in the Sassanid and Parthian eras. Furthermore, foreign experts call the unearthed city as the second and lost capital of the ‘Soloukis’ while some Iranian archeologists believe the monuments are part of the state of ‘Sirvan’. Some resources and texts link Dareh-Shahr to Mehr Jaan Ghazagh, Saabzaan, Seymareh or the city of Khosrow Parviz in the late Sassanid period, which was completely flattened by earthquakes in 248 and 344 AH. In the ruins of Dareh-Shahr, which belong to the Sassanid era, there are the vestiges of crosses, arches, ceilings, dome-shaped ceilings, alleys and passages with urban development criteria of that time. All the buildings of Dareh-Shahr are built from abraded stones and gypsum. Abundance of gypsum in Seymareh Valley and simplicity of working with it have led to their use in the Sassanid architecture. Coins discovered in this area belong to the rule of Khosrow III and his successors. Located in the south of Dareh-Shahr, at the beginning of a gorge of the same name on the outskirts of Kabir Kuh, is an ancient bridge called Gavmishan with 3 arches that were repaired in 2008. Each of its arches is at an interval of .