Located on the right bank of the Treska River, Vrelo Cave was listed as one of the top 77 natural sites in the world in the New7Wonders of Nature project.
Vrelo Cave has many stalactites including a large one in the middle of the cave known as the "Pine Cone" due to its shape. There are two lakes at the end of the cave, with one larger than the other. The smaller lake is 8 metres (26.2 feet) at its longest length and 14.92 metres (48.9 feet) in depth at its deepest point. The larger lake is 35 metres (114.8 feet) at its longest length, and 18 metres (59 feet) at its deepest point.
Though the exact depth of the cave is unknown, it is believed to be among the deepest in Europe and/or the world.