The Czech Republic's most famous cave, and the sinkhole that swallows it whole
Of the roughly 1,100 recorded caves in theMoravian Karst, the Punkva Caves draw the most visitors by a wide margin, and for good reason: nowhere else in the region combines a walking tour of cathedral-scale caverns with a boat ride along an underground river ending at the floor of the country's deepest gorge.
What the tour actually involves
Discovered in stages between 1909 and 1933 by the speleologist Karel Absolon and his team, the caves opened to the public in 1933, with the underground boat cruise running since 1920. A typical visit lasts about an hour: a walking section past dramatic stalactite and stalagmite formations, followed by a motorboat ride along the Punkva River through passages that sometimes narrow to just above head height, ending at the base of the Macocha Abyss. Along the way, the boat passes through the so-called "Fairy-tale Lakes" and the Masaryk Dome, one of the most striking chambers in the whole system.
Macocha Abyss: a hole nearly as deep as it is wide
The abyss itself, reached both from the cave floor and from two lookout platforms accessible on foot from above, plunges roughly 138–139 metres, with two small lakes at its base (an upper lake around 13 metres deep, and a lower one around 49 metres, according to research from the year 2000). Standing at the bottom and looking up at the daylight far above, or standing at the rim looking down into the void, are two completely different and equally worthwhile experiences, most visitors do both, connected by a cable car (the only one in South Moravia) that lifts you from the cave exit back up near the rim.
Booking and timing
Tours run in Czech with English materials available at the entrance; guided tours are timed and limited in group size, and tickets for weekends and the summer season are worth booking well in advance, as they routinely sell out. The caves are open year-round, though hours are reduced in the November–March off-season. Underground temperatures stay around 8°C regardless of the season, so a jacket is worth carrying even on a hot July day.
Getting there from Brno
The Punkva Caves sit near Skalní Mlýn, roughly 40 minutes' drive from Brno, in the Pustý žleb canyon about a kilometre from the visitor centre (a small tourist train covers the walk if you'd rather not do it on foot). Public transport connections from Brno run through Blansko, but onward buses to Skalní Mlýn are infrequent, often just a handful of departures a day, which makes timing a self-guided day trip around cave tour slots genuinely tricky without a car.
See both the caves and the abyss without chasing bus timetables on our Secrets of the Moravian Karst six-hour tailor-made tour from Brno.
Visiting Brno in winter? Christmas markets, St. Martin's wine, warm-all-year caves and Lednice, with official links to check what is open on your dates.
Český Krumlov is about 240 km (150 miles) from Brno, roughly 3 hours each way. See what the day looks like, the Telč stop and when to stay overnight instead.