Turbessel (Syriac: Tel Bshir, Arabic: Tell Bāshir, Turkish: Tilbeşar or Tilbaraş Kalesi) is a fortress and bronze-age tumulus in south-eastern Turkey, near the village of Gündoğan in the district of Oğuzeli, within Gaziantep Province.
While the site had been occupied since the bronze age, the fort gained importance during the Byzantine Empire and came under control of local Armenian lords in the late 11th century. Following the First Crusade, as a part of the County of Edessa it was one of the main strongholds of Frankish counts such as Joscelin. After the fall of Edessa to Zengi, it became the principal city of what remained of the County until it was eventually sold to the Emperor Manuel I Comnenus in 1150. It fell to Nur ed-Din's Muslims within the year.
- Chahan de Cirbied, Jacques (1813), "Notice de deux Manuscrits Arméniens, de la Bibliothèque impériale, n.os 95 et 99, contentant l'histoire écrit par Mathieu Eretz, et Extrait relatif à l'histoire de la première croisade" [Notice of two Armenian manuscripts from the Bibliothèque Impériale, numbers 95 and 99, containing the history recorded by Matthew Eretz, and an extract relating to the history of the First Crusade], Notices et extraits des manuscrits de la Bibliothèque Nationale et autres bibliothèques [Notices and extracts of manuscripts in the Bibliothèque Nationale and other libraries] (in French), 9, pp. 275–364
- le Strange, Guy (1890), Palestine Under the Moslems: A Description of Syria and the Holy Land from A.D. 650 to 1500, Committee of the Palestine Exploration Fund, p. 542