Kyustendil lies 525 metres above sea level in Southwestern Bulgaria . To the north, the Kyustendil valley borders the labyrinth of the Kraishte region, to the south- the steep slopes of Osogovo Mountain , to the west- the Lisets Mountain, to the northeast- the Konyavo Mountain . The river Struma crosses the plain from the north and flows down to the south and thus shapes the Zemen and Skrino defiles.The town of Kyustendil is the administrative centre of the Kyustendil region, which includes the following municipalities:

Kyustendil, Dupnitza, Bobov dol, Sapareva banya, Rila, Kocherinovo, Nevestino, Boboshevo and Trekljano. The territory of the Kyustendil region is crossed by the International Transport Corridor No.8 and is a major transport and railroad junction. Kyustendil is located 86 km away from Sofia , 23 km from the state border with the Republic of Macedonia, and 30 km from the stateborder with the Republic of Serbia .