Ctesiphon (/ˈtɛsɪfɒn/ TESS-if-on; Middle Persian: 𐭲𐭩𐭮𐭯𐭥𐭭 tyspwn or tysfwn; Persian: تیسفون; Greek: Κτησιφῶν, Attic Greek: [ktɛːsipʰɔ̂ːn]; Syriac: ܩܛܝܣܦܘܢ) was an ancient city, located on the eastern bank of the Tigris, about 35 kilometres (22 mi) southeast of present-day Baghdad. Ctesiphon served as a royal capital of the empires in the Parthian and Sasanian eras for over eight hundred years. Ctesiphon was capital of the Sasanian Empire from 226–637 until the Muslim conquest of Persia in 651 AD.