Postojna cave is the largest of several caves located in the Klokočské skály. Past the very narrow and low entrance , a large cavern opens out, and the total size of the cave is 75 sqm. The caves were used by hunter-gatherers in the Middle Stone age (at least 8000 years ago) and was occupied frequently since then, including in the late Stone Age and early Bronze Age. The archaeological findings are on display at the Turnov museum of Český ráj.

Currently, the cave is not open to the public in order to preserve the rare ecology of the cave system, including endangered species of bat.