Last updated: April 14, 2026
The Bohemian Karst (Cesky Kras) is a protected landscape area situated in the Berounka River valley, roughly 20 to 40 kilometres southwest of Prague. With an area of 128 square kilometres, it is the largest karst zone in Bohemia and holds the only publicly accessible cave system in the region: the Koneprusy Caves near the village of Koneprusy. Unlike the Moravian Karst — where the landscape is defined by its cave networks — the Bohemian Karst is as notable for its surface geology: vertical limestone outcrops, fossilised reef structures visible in road cuts and cliff faces, and dry gorges that once carried surface streams before the drainage shifted underground.
Geology and Age of the Limestones
The Bohemian Karst rests on Silurian and Devonian marine sediments deposited between approximately 440 and 380 million years ago. At that time, the area lay on the margin of a shallow tropical sea on the southern rim of the ancient continent Laurussia. Coral reefs and carbonate banks accumulated over tens of millions of years, eventually lithifying into the limestone and dolomite beds that underlie the landscape today. The sequence is one of the best-preserved Silurian-Devonian sections in Central Europe and has been studied since the 1840s.
"The Bohemian Karst contains one of the most complete Silurian-Devonian stratigraphic sections in Central Europe, spanning nearly 60 million years of ancient marine history in a single valley."
Three principal rock types appear in the Bohemian Karst sequence: grey Silurian limestone (Lochkovian stage), reef limestone and dolomite (Pragian and Emsian stages) and thin-bedded Devonian limestone containing abundant brachiopods, trilobites, crinoids and early fish remains. The GSSP (Global Boundary Stratotype Section and Point) for the Pragian Stage — the internationally agreed boundary section between two subdivisions of the Devonian Period — is located at Veletin Hill within the Bohemian Karst. The section was ratified by the International Commission on Stratigraphy in 1989 and remains the global reference point for the Pragian-Emsian boundary.
Koneprusy Caves
The Koneprusy Caves are the largest cave system in Bohemia, with approximately 2 kilometres of mapped passages arranged on three horizontal levels at different elevations within the Zlaty Kun hill. They were discovered during limestone quarrying operations in 1950 and opened to visitors in 1959. The current visitor route covers approximately 620 metres and takes roughly 50 minutes. The tour passes through three main sections: the Prochazka Hall (lower level, with active calcite formations), the Koneprusky Hall (middle level, with the most photogenic stalactite and stalagmite columns) and the upper level, which contains the only known example of cave coral formations in Czech Republic — small, branching calcite growths that form under specific water chemistry conditions.
A historically significant find inside the Koneprusy Caves was the discovery of a counterfeit coin-minting workshop dating to the late medieval period (15th century). The forgers had used the cave as a hidden workspace, leaving behind casting moulds, coin blanks and tools. The artefacts were preserved intact by the cave environment and are now held at the National Museum in Prague. The workshop is now interpreted as part of the tour.
Tetinska Skala and the Fossil Reef Outcrops
Tetinska skala is a limestone bluff above the Berounka River near the village of Tetin, notable for its vertical exposures of Devonian reef limestone approximately 40 metres high. Fossil corals, stromatoporoids (sponge-like colonial organisms) and brachiopods are visible in the rock face without excavation. The site has been studied by palaeontologists since Joachim Barrande's systematic survey of Bohemian fossils in the 1850s, and it remains a reference locality cited in European stratigraphic literature. The bluff is part of the Bohemian Karst protected zone and cannot be sampled without permit, but surface examination of fallen blocks and natural sections is unrestricted.
The Srbsko Gorge and Dry Valley Network
The Srbsko Gorge runs for approximately 3 kilometres along a former river channel that now carries water only during heavy rainfall. The valley was cut by a surface stream that later captured by the underground drainage system as the karst developed. Its walls expose a sequence of alternating limestone and shale beds representing transitions between shallow marine and deeper water environments during the Silurian period. Walking routes through the gorge are marked and follow the valley floor; limestone outcrops with visible fossil content line both sides throughout. Several small caves — none currently open to the public — are visible in the valley walls, representing earlier stages of the karst development before the drainage deepened to its current level.
Karst Hydrology of the Berounka Valley
The primary drainage of the Bohemian Karst flows through the Berounka River, which runs along the southern edge of the protected area. Within the karst zone, several smaller streams disappear underground during dry periods through swallow holes (ponors) in valley floors and re-emerge as springs (vyvere) further downstream. The most documented underground flow path runs beneath Zlaty Kun hill from a swallow hole near Koneprusy village to a spring in the Berounka bank, a straight-line distance of roughly 1.2 kilometres. Tracing experiments using fluorescent dye confirmed the connection in the 1970s; the passage itself has not been penetrated beyond the first 200 metres due to sumps filled with water.
Access and Context
The Bohemian Karst is accessible by train from Prague main station to Beroun (45 minutes), with local bus connections to Koneprusy village near the cave entrance. Marked hiking trails connect the main geological and palaeontological sites across the protected area. The Koneprusy Caves are the only site with paid guided tours; all surface outcrops and fossil localities are accessible on foot without charge. For current tour times: Czech Cave Administration — Bohemian Karst.
