Jaskinia Ostrężnicka

Ostreznicka Cave

Useful Information

Location: 42-253 Złoty Potok.
On road 793 between the villages Złoty Potok and Żarki. Turn off into single lane gravel road to Ostrężnik halmlet signposted for Zamku Ostrężnik. Small parking lot, 10 minutes walk.
(50.6749898, 19.4011468)
Open: no restrictions.
Fee: free.
Classification: SpeleologyKarst Cave
Light: bring torch
Dimension: L=98 m, A=350 m asl.
Guided tours: self guided
Photography: allowed
Accessibility: no
Bibliography: Joanna Czerwik-Marcinkowska (2011): Algae and cyanobacteria in caves of the Polish Jura, Polish Botanical Journal 56(2), January 2011. researchgate
Address: Jaskinia Ostrężnicka, 42-253 Złoty Potok.
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.


14th century castle built.
1960 declared a Forest Reserve.


Jaskinia Ostrężnicka (Ostreznicka Cave) is located in the Dolina Wiercicy valley near Ostrężnik village, after which it was named. The small cave is located inside a limestone rock which is famous for the ruined castle Ruiny Zamku Ostrężnik. This mysterious castle is located in the woods on a hill with a rock, another limestone rock adjacent to the castle contains the cave which were, according to legend, connected by tunnels. The castle had upper and lower ward plus one or two outer wards, remains are visible in the forest. The lower ward had a moat, which was water filled. However, there are no documents about the castle and so it is unknown who built it and when. Most likely it was built in the 14th century, a guess based on the design of the castle.

There are several legends about the castle. According to one the doors to the sacristy of the church in Złoty Potok originate from the castle. Another legend tells, the castle was never completed, King Casimir the Great abandoned its construction due to other nearby castles and watchtowers. This is most likely nonsense, the upper castle has 1500 m², and the lower castle 7200 m², the walls are up to 2 m thick. Such an investment at an important strategic place would not have been abandoned in favor of less important neighbours. Another legend tells the castle was owned by Wojciecha z Potoka (Adalbert of Potok). He is mentioned as a courtier of Duke Władysław Opolczyk and owner of the area in 1386. According to the legend he was a robber knight and attacked merchants travelling on the route to Gdańsk - Kalisz - Kraków.

The cave is a labyrinth which riddles the limestone rock. It has five entrances, one on the northern side, two on the northwestern side and two on the southern side. There is also a second entrance on the northern side, which is actually not connected to the cave. The northern entrance is the most spectacular one, rather huge and the separation into two passages right behind the portal is clearly visible from outside. It looks like two small portals located inside a big one. The cave is horizontal and has a clayey and sandy floor. The trails across the forest and to the castle also lead to the cave and so it is popular and visited by many people, especially on good weather weekends during the summer. However, the passages connecting the entrances are generally narrow and low, so crawling is required.

The forest surrounding the cave is full of limestone rocks with small caves and natural bridges. Jaskinia Wiercica is located 750 m east of the hamlet, Jaskinia Wierna only 100 m. 1 km to the north at the road is the Diabelskie Mosty (Devils Bridge) a fracture cave. After 100 m the road to Siedlec branches off to the left, after 600 m is the Brama Twardowskiego, a huge natural bridge on the right side of the road. There are also the two karst springs Źródła Elżbiety i Zygmunta (springs of Elżbieta and Zygmunt) which provide the water for a trout farm a little further towards Złoty Potok. Grota Niedźwiedzia on the other side of the road is not the more famous Jaskinia Niedzwiedzia, which is a show cave located 200 km to the west at the border to the Czech Republic. Niedźwiedzia means Bear so these are "bear caves", a generic name which is used quite frequently and always prone to mixup. And there are several more caves, the area is definitely worth a visit, preferable on a hike.