At best, we associate the underground with the cellars and dungeons of the fortresses open to the public, old mine pavements or the mysterious tunnels of the Riese complex in the Sowie Mountains (Owl Mountains). Meanwhile, some of the most beautiful attractions of Lower Silesian nature are hidden just under a thick layer of earth, in the depths of caves that have only been partially explored by speleologists. Among those that were not only researched and described, but also put into tourist traffic, the Bear Cave in Kletno is the most visited. This longest cave in the Sudetes, and at the same time one of the longest and deepest caves in Poland, took its name from the large amounts of cave bear remains found in it, extinct at the end of the last ice age, about 28,000 years ago. For millions of years, the waters of Kleśnica dug underground corridors, creating amazing shapes that the dripstone form of the cave took. It is in order to admire the various forms of infiltration – stalactites, stalagmites, helictites, cascades and draperies – created as a result of calcium carbonate crystals deposited in the form of calcite crystals, that every year thousands of visitors go to the cave on a specially prepared tourist route. The tour, which lasts about an hour, allows you not only to admire the natural beauty of the Bear’s Cave, but also to feel like the first explorers from the 1960s for a moment. Much earlier, in the second half of the In the 18th century, the Radochowska Cave was discovered, located in the Złote Mountains near Lądek-Zdrój, a popular health resort. It was a tourist destination before the war, from the very beginning it attracted not only speleologists and zoologists, but also mountain enthusiasts and patients coming to nearby sanatoriums. Although today we do not find such a wealth of infiltrations in Radochów as in the Bear’s Cave, as many as 90 species of animals live here (including several species of bats wintering in the cave and representatives of water fauna living in smaller and larger cave lakes). Seekers of caves and cavers will find at least a few other similar natural attractions in the Sudetes, incl. Dziurawy Kamień Cave near the route from Sobieszów to Chojnik Castle, Northern Wielka Cave near Wojcieszów or the Salt Cave in marble at the foot of Czerniec in the Bystrzyckie Mountains, resembling an underground tunnel.