Nagorno-Karabakh is a landlocked region in the South Caucasus, lying between Lower Karabakh and Zangezur and covering the southeastern range of the Lesser Caucasus mountains. The region is mostly mountainous and forested. The region is usually equated with the administrative borders of the former Nagorno-Karabakh Autonomous Oblast comprising an area of 4,400 square kilometres (1,700 sq mi). The historical area of the region, however, encompasses approximately 8,223 square kilometres (3,175 sq mi).