Şanlıurfa, formerly Urfa, or Edessa, Arabic Ar-ruhāRuhā, city, southeastern Turkey. It lies in a fertile plain and is ringed by limestone hills on three sides. The city is very old and controls a strategic pass to the south through which runs a road used since antiquity to travel between Anatolia and northern Mesopotamia. The modern name derives from the early Aramaic name, Urhai, which was changed to Edessa when the town was refounded as a military settlement in the 3rd century BC. Freeing itself from imposed Hellenism, Edessa, as capital of the principality of OsroeneOsroëne, was a major centre of Syrian culture; it figured prominently in the conflicts between Parthia and Rome.

Christianity reached Edessa about AD 150, and the city became the seat of what was soon the most important bishopric in Syria. A sizable body of early Christian literature in the Syriac language was produced at Edessa.

After having been captured by the Sāsānid Persians on more than one occasion, Edessa was taken by the Arabs about 638. Thereafter it saw many changes of rule, including occupation by the crusaders in 1098, until it was annexed to the Ottoman Empire at some point between 1516 and 1637. It then remained Turkish, except for a short occupation by forces of the Ottoman governor of Egypt, Muḥammad ʿAlī Pasha, in the late 1830s.

The city’s monuments include the ruins of an ancient citadel situated on one of the hills overlooking the town, part of the old city walls, flood-prevention works built in the 6th century by the Byzantine emperor Justinian, and the 17th-century madrasah (religious school) and mosque of ʿAbd ar-Raḥmān. Modern Şanlıurfa is a local market for the agricultural and livestock products of the surrounding region. The main exports are butter and wool. The city is linked by main roads with Gaziantep to the west, Mardin to the northeast, Adiyaman to the northwest, and northern Syria to the south. Pop. (19902000) 276385,528588.