There is one interesting natural phenomenon in Kopaonik,Serbia.
This is the lake the islands sail through. The lake is about 60m in diameter and the largest island is 15m long and overgrown with vegetation, and there are even a few tall trees on it. In addition to this island, there are several smaller ones, and several have been destroyed by bathers.
Floating islands are a real attraction for all tourists who visit this lake, because the islands move when the wind blows, and visitors can also "ride" them.
Semetes Lake is also specific because its depth cannot be measured, because the underwater springs from which the lake receives water are so deep and wide that they themselves are part of it.
Gazeboes are the ancient owners of Lake Semetez, and the lake was recently stocked.