The tunnel of the Schwarzenberg channel at the edge of the forest beyond the car parking in form of the Neo- Renaissance stone portal from 1823 is an entrance into the 389 m long floating tunnel. The Schwarzenberg floating channel is a unique European water-work connecting the Vltava catchment area with the Danube. The construction designed by the engineer Josef Resenauer has a total of 58 km in length, of which 37 km are at the territory of Bohemia.
The channel has influenced importantly the history of the whole territory. Many villages (e.g. Josefův Důl, Jelení Vrchy) occurred in the originally unsettled area, offering job to workers on the channel construction, the number of whom amounted up to 1 200. Subsequent timber floating through the channel was also ensured by almost 1000 people, whose tasks consisted in timber throwing, in the inspection of smooth and fluent timber floating through the channel with hooks in hands or in pulling of the logs from the channel. During winter seasons the logs and stems were brought down to the channel on the sleigh and with the spring melting were floated down the channel.
On the other side, the channel construction made accessible 14 000 hectares of woods. About one square kilometre a year was cleared. Over the 100 years, some 7 million cubic metres of timber were transported to Vienna. Non-endemic spruce from lowlands was planted into the clearings, unable to resist severe climatic conditions of the mountains. We have inherited these poorly resistant forests with all the consequences.