Mount Tupižnica stretches between Knjaževac and Boljevac. The highest peak of Tupižnica is located at 1160 meters above sea level, and the mountain itself is mysteriously beautiful and insufficiently explored. The most frequent visitors to the mountain are mountaineers and paragliders.
It is also called the “island mountain”, because it is surrounded on all sides by a lowland. Tupižnica is known for dozens of speleological objects, the most famous of which are the “tupižnica icicle” and “David’s doom”, about a hundred meters deep.