The border between the Syrian Arab Republic and the Republic of Turkey is about 909 kilometres (565 mi) long, and runs from the Mediterranean Sea in the west to the tripoint with Iraq in the east. It runs across Upper Mesopotamia for some 400 kilometres (250 mi), crossing the Euphrates and reaching as far as the Tigris. Much of the border follows the Southern Turkish stretch of the Baghdad Railway, roughly along the 37th parallel between the 37th and 42nd eastern meridians. In the west, it almost surrounds the Turkish Hatay Province, partly eating the course of the Orontes River and reaching the Mediterranean coast at the foot of Jebel Aqra.

The Tigris is the eastern of the two great rivers that define Mesopotamia, the other being the Euphrates. The river flows south from the mountains of the Taurus in Turkey, then through the Syrian and Arabian Deserts, emptying into the Persian Gulf.