The Prebisch Gate natural monument - one of the most famous rock formations in the Czech Republic
Located 3 km from Hřensko, near the German-Czech border, the rock gate is the symbol of the Bohemian Switzerland National Park. With a height of 16 m, a span of almost 27 m and an arch width of 7-8 m, it is the largest sandstone rock gate in Europe.
Fascinating views can be enjoyed from the accessible rocks above the "Sokolí hnízdo" restaurant (building from 1881). The Prebisch Gate has been attracting visitors since the end of the 18th century. The large number of visitors led to increased erosion in the upper parts and damage to the gate. For this reason, access to the gate for tourists was banned in 1982. The aim of the protection measures is to maintain the current condition and natural development of the sandstone cliffs and to minimise negative anthropogenic influence.
In 2009, the Prebisch Gate was shortlisted among the "New Seven Wonders of the World", where it was one of the 77 semi-finalists. Every year, more than 200,000 visitors from home and abroad visit this natural monument.
The monumental rock bridge, however, fascinates not only the visitors who climb up to the Prebisch Gate, but also scientists. For years, they have been racking their brains as to why the Prebis Gate did not collapse long ago. The rock arch is actually too thin and brittle to withstand the stress of its own weight and the repeated expansion and contraction of the rock due to fluctuations in the ambient temperature. The scientists concluded that the Prebisch Gate is actually formed by two independent rocks (see the illustration with the Prebisch Gate showing these two rocks in different colours). This means that the arch is not under so much tension that it breaks. It would be different if the rock arch were firmly connected to the rock mass on both sides. Nevertheless, the arch is constantly monitored and measured with special measuring devices that register every movement. Experts also observe the decay of the gate's surface due to weathering processes caused by long-term air pollution and the rock's reactions to acid rain.
Fascinating views can be enjoyed from the accessible rocks above the "Sokolí hnízdo" restaurant (building from 1881). The Prebisch Gate has been attracting visitors since the end of the 18th century. The large number of visitors led to increased erosion in the upper parts and damage to the gate. For this reason, access to the gate for tourists was banned in 1982. The aim of the protection measures is to maintain the current condition and natural development of the sandstone cliffs and to minimise negative anthropogenic influence.
In 2009, the Prebisch Gate was shortlisted among the "New Seven Wonders of the World", where it was one of the 77 semi-finalists. Every year, more than 200,000 visitors from home and abroad visit this natural monument.
The monumental rock bridge, however, fascinates not only the visitors who climb up to the Prebisch Gate, but also scientists. For years, they have been racking their brains as to why the Prebis Gate did not collapse long ago. The rock arch is actually too thin and brittle to withstand the stress of its own weight and the repeated expansion and contraction of the rock due to fluctuations in the ambient temperature. The scientists concluded that the Prebisch Gate is actually formed by two independent rocks (see the illustration with the Prebisch Gate showing these two rocks in different colours). This means that the arch is not under so much tension that it breaks. It would be different if the rock arch were firmly connected to the rock mass on both sides. Nevertheless, the arch is constantly monitored and measured with special measuring devices that register every movement. Experts also observe the decay of the gate's surface due to weathering processes caused by long-term air pollution and the rock's reactions to acid rain.