Burel Valley (Bulgarian: Бурелска котловина) is situated in western Bulgaria and is the first and westernmost of the chain of eleven Sub-Balkan valleys. The valley is enclosed between the western slopes of the Chepan division of the Balkan Mountains to the north, the small mountain ranges of Zavalska Planina and Viskyar to the south, and Greben to the west, already on the territory of Serbia. To the east the watershed between the rivers Gaberska and Slivnishka, as well as the Aldomirovtsi Heights form the boundary with the much larger Sofia Valley.
Burel Valley spans a territory of 172 km in Bulgaria. Its length from northwest to southeast is 15 km; the width varies between 7 and 10 km. The average altitude is 765 m; the highest point is mount Vidim (965 m).