The Vltava river channel between Loučovice and Vyšší Brod is full of large boulders, including the characteristic giant boulders with hollows. Here, the canyon of the river forms an enchanting place where the wilderness of Mother Nature and the power of the water element takes your breath away. The magic of this site inspired those who produced the film named Rafťáci. It is precisely the stretch between Loučovice and Vyšší Brod where the natural settings enabled one of the most difficult boating routes in the world to be formed. Called Čertovy proudy (Devil’s Streams), it is normally impossible to navigate for watermen, but the amount of water can be boosted thanks to the dam of Lipno so professionals and experienced boaters can enjoy rapids of the greatest difficulty. The site also sees races on white water organised on a periodical basis. In such cases, the flow rate is increased to 20-30 m³/s, while about 2 m³/s is a standard value.