Moravian Karst: Underground World North of Brno

Last updated: April 14, 2026

The Moravian Karst protected landscape area lies roughly 15 kilometres north of Brno along the eastern margin of the Bohemian-Moravian Highlands. Covering 94 square kilometres of deeply eroded Devonian limestone, it contains more than 1,100 catalogued cave cavities, an extensive network of subterranean rivers and the most visited karst site in Czech Republic. The landscape above ground is characterised by dry valleys, limestone pavements, sinkholes and isolated rock outcrops, while below the surface a sequence of cave corridors, halls and shafts extends to depths exceeding 100 metres in several systems.

The Macocha Gorge

At the heart of the Moravian Karst stands the Macocha Gorge (Propast Macocha), a collapsed doline measuring 174 metres in length, 76 metres in width at its widest point and 138.5 metres from the upper rim to the bottom lake. It formed when the roof of an ancient cave chamber gave way, leaving a vertical pit that now channels surface water directly into the Punkva River below. Two viewing platforms on the rim — the upper (accessible by forest path) and lower (accessible from within Punkva Caves) — look into the gorge from different elevations. The lower platform sits at an overhang just 87 metres above the bottom and provides a view directly along the axis of the pit. At the base, two small lakes occupy the lowest point of the gorge floor, fed by rainwater and runoff from the surrounding limestone.

Punkva Caves and the Underground River Tour

The Punkva Caves (Punkevni jeskyne) form the most-visited cave system in Czech Republic, with approximately 180,000 visitors annually. The tour follows the course of the Punkva River through approximately 1.5 kilometres of illuminated galleries, passing through chambers named for their formations: the Masaryk Dome, the Krizova Hall and the Willow Room. After the walking section, visitors board flat-bottomed boats for a 400-metre ride along the underground river to the foot of the Macocha Gorge. Looking upward from the boat, the walls of the gorge converge to a narrow strip of sky 138.5 metres above.

The river itself enters the cave system near the village of Skalny Mlyn and re-emerges at the spring in the valley of Punkevni udoli. Its underground course passes through both the Amaterska Cave system and the Punkva Caves, making it one of the longest continuously documented underground river sections in Central Europe at roughly 12 kilometres.

Katerinska Cave

Katerinska Cave (Katerinska jeskyne) sits 1.5 kilometres south of the town of Blansko and is accessed via a short walk from the road. Its main hall — known as the Katedrala — measures approximately 97 metres in length, 44 metres in width and 22 metres in height, making it the largest unsupported cave dome in Central Europe. The floor is level and partly covered with flowstone deposits. Stalactites hang from the ceiling in dense formations, the largest reaching 4 metres in length. A separate section of the cave contains the Bamboo Grotto, named for thin, hollow stalactites (cave soda straws) that grow downward from hairline fractures in the ceiling and resemble bamboo canes. These formations are fragile and rarely exceed 4 mm in diameter despite lengths of up to 1 metre.

The cave was known locally since at least the 18th century but received systematic scientific study from the mid-19th century onward. A notable glacial-era deposit of cave bear bones was documented near the entrance in the 1890s, later removed and catalogued at the Moravian Museum in Brno.

Sloupsko-Sosuvske Caves

The Sloupsko-Sosuvske cave complex in the northern section of the Moravian Karst is the most vertically extensive publicly accessible cave system in Czech Republic, with a vertical range of 110 metres. The tour descends through a sequence of different geological zones: dry upper galleries with older speleothems (stalactites and stalagmites), active lower passages with flowing streams and a section of flooded tunnels visible through glass. The complex consists of two originally separate cave systems — Sloupska Cave and Sosuvska Cave — connected by an artificial tunnel in the 20th century to create a continuous visitor route. Paleontological deposits in the Sloupska section have yielded remains of cave bear (Ursus spelaeus), cave hyena and woolly rhinoceros from the last glacial maximum.

Balcarka Cave

Balcarka Cave, located in the eastern part of the Moravian Karst near Ostrov u Macochy, is noted for the density and colour variation of its speleothem formations. Unlike most Moravian Karst caves, which tend toward white and grey calcite, Balcarka contains ochre and orange aragonite formations alongside white calcite stalactites. The colour difference results from iron oxide and manganese inclusions in the rock during periods of different groundwater chemistry. The cave is one of the smaller public sites (tour route approximately 450 metres) but consistently cited in speleological literature for formation quality.

Visiting the Moravian Karst

All publicly accessible caves in the Moravian Karst are administered by the Czech Cave Administration. Tickets are purchased at each cave separately; there is no combined pass. The Macocha Gorge upper rim viewpoint is free of charge and reached via a marked trail from Blansko or the village of Vilémovice. The lower viewpoint inside Punkva Caves is part of the paid tour.

• Punkva Caves: Tours depart approximately every 30 minutes; the boat section requires booking in advance during July and August.
• Katerinska Cave: Several tours per day; the cave maintains a constant temperature of 8°C year-round — a jacket is recommended regardless of season.
• Sloupsko-Sosuvske: Longer vertical tour; physically demanding descent and ascent — not suitable for visitors with limited mobility.
• Balcarka: Shorter tour; suitable for all ages; no advance booking typically required outside peak summer weeks.

Further information on opening hours, ticket prices and access: Czech Cave Administration — Moravian Karst.