Kletno Uranium Mine

The Kletno Uranium Mine (say "KLET-no") is an underground tourist route in a former adit on the slopes of the Śnieżnik Massif in the Sudetes, southwest Poland. Between 1948 and 1953, under Soviet supervision, uranium ore was mined here for the Soviet nuclear program. Today the guided tour leads through colorful tunnels lined with fluorite, amethyst and quartz – and tells a little-known Cold War story from the Polish–Czech borderlands.

From medieval miners to the atomic age

Mining in the area goes back centuries: the first documented works date from the late 15th century, and copper ores (azurite and malachite) were mined in Kletno in the 15th and 16th centuries, along with silver-bearing galena and iron ore.

Uranium was discovered on July 15, 1948, during work in medieval adits. A Soviet geological service ran the operation with Polish workers; in reports uranium was simply called "metal." Output peaked in 1948–1950 and ended in early 1953. The mine eventually had about 37 km of tunnels. Fluorite was mined until 1958, and the entrances were blasted shut in 1959. The tourist route in adit no. 18 opened in 2002.

What the tour is like

• Visits are guided only, in groups of up to 25 people, and last about 45 minutes.
• It is about 7°C (45°F) underground year-round – bring a warm layer and closed shoes.
• You will see fluorite, amethyst, quartz, barite and malachite, plus old lamps, maps and mining equipment.
• The operator states that the route is safe in terms of radiation.
• Audio guides in English, German and Czech are available, as the live tour is in Polish.

An adit is a horizontal tunnel driven into a hillside, so there is no elevator ride or deep shaft – the route is fairly level, though uneven and damp in places. The uranium ore was removed from adit no. 18, which is one reason it could be opened to visitors.

Is it worth visiting? If you are interested in Cold War history or minerals, definitely – it pairs well with the nearby Bear Cave.

Opening hours and tickets

As of October 2026, per kletno.pl:

• Tuesday–Sunday, tours at 10:30, 11:30, 12:30, 13:30, 15:30 and 16:30;
• Monday – closed;
• check winter hours online before traveling.

Tickets cost 55 PLN (standard) and 40 PLN (reduced). Capacity is limited, and only online booking guarantees your chosen time. Phone: +48 889 785 118 (daily 8 a.m.–6 p.m.).

How to get there

The mine is in the village of Kletno, near Stronie Śląskie, in the Kłodzko region. It is about 2 hours by car from Wrocław, the nearest major city and airport, and about 40 minutes from Kłodzko. There is free parking at the entrance. Pets are not allowed underground.

Nearby

A few kilometers away is the Bear Cave (Jaskinia Niedźwiedzia), one of Poland's finest show caves – book ahead and visit both on the same day. Trails lead from Kletno up Śnieżnik (1,425 m), and the spa town of Lądek-Zdrój is close by.