Caves, Grottoes are voids formed in easily dissolving rocks such as limestones, dolomites and gypsum. Most phenomena of this type such us caves, grottos, funnels or crevices occur in the Kraków-Częstochowa Upland, because it is largely built of Jurassic limestones. There you can admire numerous, lonely white limestone hills called inselbergs, numerous caves in the vicinity of Ojców and the diverse Prądnik Valley.