Tur Abdin (طور عبدين, Tor, Turabdium, Ṭūr ʿAḇdīn) is a hilly region situated in southeast Turkey, including the eastern half of the Mardin Province, and Şırnak Province west of the Tigris, on the border with Syria and famed since Late Antiquity for its Christian monasteries on the border of the Roman Empire and the Sasanian Empire. The area is a low plateau in the Anti-Taurus Mountains stretching from Mardin in the west to the Tigris in the east and delimited by the Mesopotamian plains to the south. The Tur Abdin is populated by more than 80 villages and nearly 70 monastery buildings and was mostly Syriac Orthodox until the early 20th century. The earliest surviving Christian buildings date from the 6th century.
The name "Tur Abdin" is ܛܘܪ ܥܒܕܝܢ. Tur Abdin is of great importance to the Syriac Orthodox Assyrians, for whom the region used to be a monastic and cultural heartland. The Assyrian/Syriac community of Tur Abdin call themselves Suryoye, and traditionally speak a central Neo-Aramaic dialect called Turoyo.
The town of Midyat and the villages of Hah, Bequsyone, Dayro da-Slibo, Saleh (with the old monastery of Mor Yaqub), Iwardo (with Mor Huschabo), Anhel, Kafro, Arkah (Harabale, with Dayro Mor Malke), Beth Sbirino, Miden (Middo), Kerburan, Binkelbe with Mor Samun Zayte and Beth Zabday (Azech) were all important Syriac Orthodox settlements among with countless other villages. Hah has the ancient 'Idto d'Yoldath-Aloho, the Church of the Mother of God.
The Assyrian king Adad-nirari II, who came to throne in the late 10th century BCE, drove the Arameans out of the area. In the 9th century BCE the Assyrian King Ashurnasirpal II described crossing the plateau of Tur Abdin (which he calls "Kashyari") on his way to attack the region of Nairi, more than once. He erected a monument in Matiate, modern-day Midyat in Tur Abdin, which remains to be found. His successor, the Assyrian king Shalmaneser III, also crossed Tur Abdin.
Most ancient monuments in Tur Abdin are Christian, but as attested by the Assyrian king Ashurnasirpal II, the area has a pre-Christian history.