Rumkale (lit. Roman Castle), also known as Urumgala, is a fortress on the Euphrates, located in the province of Gaziantep and 50 km west of Şanlıurfa. Its strategic location was already known to the Assyrians, although the present structure is largely Hellenistic and Roman in origin. It is said that John, an apostle of Jesus, lived in Rumkale during Roman times. The site was occupied by various Byzantine and Armenian warlords during the Middle Ages. During the 12th century, it also became the seat of an Armenian bishop. In 1179, a synod took place in Rumkale, attempting a compromise between the Greeks and the Armenians. From 1203 to 1293, it served as the residence of the Catholicos of the Armenian Church. In 1293, it was captured by the Mamluks of Egypt following a protracted siege who th