Tucked deep into the slopes of Mount Beljanica in Eastern Serbia, stands the Veliki Buk ("The Great Hum") or Lisine Waterfall.

The waterfall originates from a small river named Vrelo, the right tributary of the Resava river. It's located at more than 1,000 feet (380 meters) above sea level and is 82 feet (25 meters) tall. The waterfall is one of the largest in all of Serbia and was formed due to natural sinter (tufa) accumulation.

A shallow pond with crystal clear turquoise water forms at the foot of the falls, surrounded by tufa blocks. The amount of water flowing through the waterfall depends on the weather conditions and seasons, with spring being the best time to visit. The falls and the surrounding landscape is protected as an exceptional natural monument by the Republic of Serbia.