Súľov rocks (National Nature Reserve), built of coarse conglomerate, calcite and sand rocks, create many bizarre terraces, balconies and overhanging rock forms. That is why they are also called the Slovak Dolomites. Due to different climatic factors, the rocks have been drammatically altered and natures sculpturing of the conglomerate stones have created holes, towers, needles and various other features. They have been given the imaginative appellations of, amongst others: Owl and Little Owl, Indian, Spruce Tree, Sleeping dinosaur and Organs. Today it is hardly possible to distinguish the remains of Súľov Castle, dating back to the 15th century, amongst the conglomerate Súľov rocks. The castle was never strategically important, but its location is interesting, as it was the castle with the most difficult access route in Slovakia (also called "Eagle nest").