The natural monument is a cave on the left bank of the Semi River, formed in Barremian limestone and rich in stalactites, stalagmites, travertines and large gours. The cave's entrance opens at the bottom of an asymmetrical funnel. The entrance is 6 meters wide; over the first 80 m the floor slopes at 12–15°, developing steps 1–1.5 m deep toward the end. 125 meters from the entrance is a 5-meter drop, adjoining a large chamber (30 × 25 m). In the Middle Ages the cave was used as a refuge. Location: Tskaltubo municipality, near the village of Kumistavi, left bank of the Semi River, 287 meters above sea level.