The Rudice Sink: where the Jedovnický Stream vanishes underground

The Rudice Sink (Rudické propadání) is a spot between Jedovnice and Rudice where the Jedovnický Stream plunges into a rock face and disappears underground. Below ground it tumbles down a cascade of waterfalls, the highest measuring 35 metres, making it the tallest underground waterfall in the Czech Republic. It doesn’t resurface until more than 12 kilometres later, at Býčí skála. The caves themselves aren’t open to the public, but you can see the sinkhole itself from a viewpoint along the Jedovnice Ponds – Rudice Sink nature trail, which also follows the green-marked hiking route. Entry is free and the site is open all year round.

QUICK LINKS 🌊 What you’ll see · 🚶 Getting there · 🕳️ What lies underground · 🔦 Can you go inside? · 🗺️ What to combine it with · ❓ FAQs

What you’ll see

The Jedovnický Stream flows in from the Jedovnice ponds and vanishes underground at a rock face. There’s a freely accessible cave with a spacious dome right at the sinkhole, with two entrances — one reached via a footbridge over the stream. On the slope nearby, look out for slag from an old ironworks, a reminder that the Rudice area was a centre of mining and metalworking for centuries.

The stream carries the most water after heavy rain or during the spring thaw — that’s when the sinkhole is at its most dramatic.

Getting there

The easiest approach is along the green-marked hiking trail linking Jedovnice and Rudice, which passes right by the sink. The Jedovnice Ponds – Rudice Sink nature trail follows the same route. You can start your walk:

• in Jedovnice, by the ponds, where the nature trail to the sink begins,
• in Rudice, by the windmill, which also houses an information centre.

If you fancy a loop, the walk can easily take in both villages. By car, most visitors head to Jedovnice or Rudice, where you can park in the village itself — there’s no official car park right at the sink. The path through the woods is unpaved, so wear sturdy footwear; after rain, it can be tough going with a pushchair.

Please note: Rudice Sink is a national nature monument (designated in 1990). Stick to the marked path, don’t climb into rock fissures or into the water, and don’t approach the sinkhole when water levels are high. For more, see our article Rules in the Moravian Karst Protected Landscape Area.

What lies underground

The most fascinating part of the sink is invisible from above. Beneath the sinkhole begins the Rudice Sink – Býčí skála cave system, the second-longest in the Czech Republic. Depending on the source, it measures over 12 km (per Rudice village records) or over 13 km (per more recent surveys).

• Waterfalls: the stream tumbles down a series of steps to a depth of around 90 metres. The tallest waterfall measures 35 metres, making it the highest underground waterfall in the country.
• Rudice Abyss: at 153 metres deep, it’s the deepest underground abyss in the Czech Republic.
• Giant’s Dome (Obří dóm): one of the largest cave chambers in the country.
• The water’s journey: beneath the Rudice plateau, the stream flows through long passages before re-emerging at Býčí skála in the Josefov Valley. We cover this in our article Josefov Valley and Býčí skála.

Exploration of the system began as far back as 1802 under Count Hugo Salm, and cavers are still discovering new passages to this day. For more on how the whole karst region formed, see our article How the Moravian Karst was formed.

Can you go inside?

Not normally. The caves of Rudice Sink are not open to the public. The only way in is via a caving course run with certified instructors, organised by the local caving group Speleo Rudice (speleorudice.cz). According to Kudy z nudy, a course costs 1,500 Kč (approx. €60 — this is a rough guide only, as exchange rates fluctuate) per person, runs year-round except in late September/early October, and requires advance booking. Expect climbing, water and mud — this is not a guided tour like at Punkva Caves (Punkevní jeskyně).

You can, however, visit Býčí skála, part of the same system, on the open days organised by cavers. In 2026, these took place over three weekends in June.

What to combine it with

• Rudice: a windmill with an information centre and geopark.
• Rudice geodes: hollow stone spheres lined with crystals, found in the area around Rudice.
• Jedovnice: the Olšovec pond, with swimming and lakeside restaurants.
• Křtiny Valley: where the water from the sink continues its underground journey.
• By bike via Jedovnice — see our Blansko–Křtiny–Jedovnice cycling route.

Rudice Sink is also one of five caves accessible only via caving expeditions — that is, with a caver, in a helmet, and without walkways — see Caves without a guided tour. It’s also the only sink in the Czech Republic where the stream flows directly into the cave through its portal — more in our article Karst features of the Moravian Karst.

FAQs

Is there an entry fee at Rudice Sink? No. The sinkhole is freely accessible from the hiking trail, all year round, free of charge.

Can you see the 35-metre waterfall? No — it’s deep underground and off-limits to the public. From the surface, you can see the point where the stream disappears into the rock.

How do you get to the sink? Follow the green-marked hiking trail from Jedovnice or Rudice. The Jedovnice Ponds – Rudice Sink nature trail follows the same route.

Is the route suitable for children? Yes, it’s a woodland walk along a marked path. An all-terrain pushchair is advisable, as the path is unpaved.

Where does the Jedovnický Stream reappear? At Býčí skála cave in the Josefov Valley, over 12 kilometres downstream underground.

Can you visit the cave with a guide? Only by joining a caving course with Speleo Rudice (roughly 1,500 Kč per person, booking required in advance). There are no standard guided tours here.

Information verified as of 18. 9. 2026. Sources: Rudice Village: Rudické propadání, Wikipedia: Rudické propadání, Kudy z nudy: Rudické propadání, Stará škola: Rudické propadání, Kudy z nudy: Open Days at Býčí skála Cave 2026.