The town of Pernik is situated 710 meters above the sea level, along both banks of the Struma River, between the mountains of Vitosha and Ljulin. It is the largest town in Southwestern Bulgaria after capitol Sofia. The town has almost 100 000 inhabitants and is regional center and the largest coal output center in Bulgaria. It is settled at 30 km. to the southwest of Sofia, 59 km. to the northeast of Kyustendil and 70 km. to the north of Blagoevgrad. Through the town’s territory passes international E 79 highway, also another important route Sofia-Thessalonica-Skopje traverses the region. The town of Pernik has a linearly developed structure and is situated primarily in the lowlands along the Struma River. Its favorable climate and its vast semi-mountain pastures have created suitable conditions for living, so it has been inhabited since ancient times. There are enough natural and cultural resources to fulfill the needs of the local residents, the residents of Sofia and the sporadically visiting foreigners and Bulgarians from other parts of the country. The most important industries, which develop Pernik, are: black metallurgy, production of electrical and thermal energy, machinery construction, metal processing, coals mining. Borovets Building provides all construction works with most quality shaped steel, concrete and iron, produced in this area. National park Vitosha surround Pernik, as well as Rudartsi spa resort and the longest cave in Bulgaria – Duhlata.