On the road Knjaževac – Pirot, near Kalna, there is a waterfall Bigar, a natural attraction that must be seen.
Bigar Waterfall is a natural treasure declared a natural monument of nature. It was named after the type of substrate in which the stream cut its bed.
In the vicinity of the waterfall, a small parking lot has been arranged and benches have been set up next to clear, icy and bright water, which can also be drunk from a spring below the twenty meters high waterfall.
Above the waterfall, hidden in dense vegetation, there are small limestone lakes of unusual blue-green color. They can be reached when you turn right in front of the “Bigar” waterfall along a pedestrian path.
A hiking trail, about 3km long, leads to the Monastery of Sv. Onuphrius and the originator of vice, a place that the people of this region call “crazy spring”. Under the cascading lakes, six mills used to grind grain. Although the stone no longer turns, Bigar is a real gem of the Stara Planina tourist offer.
During the winter, Bigar stream freezes and leaves visitors breathless.