Cave "womb" is an ancient Thracian sanctuary of an existing 20th century BC, located in the "Kaya Tangardak" Nenkovo the village, just 20 km. northwest of Kardzhali. It is unique not only in our country but also worldwide. It was reached by a well marked trail not too steep for an hour - hour and a half on it are numerous alcoves and nooks for relaxation. Initially, the cave was a natural opening in the horizontal scale, which has subsequently been shaped by human hand at the bottom of the cave shrine was built more than a meter high, every day for a certain part of the day for a few minutes it falls sunbeam and remain there for minute or two, a slight flicker, this phenomenon represents the act of fertilization, the rebirth of life, symbolizes the marriage between rock and the sun. The opening of the ancient temple is 2.5 meters high 3m.i wide, its depth reaches 22 m., It comes from water that collects at the bottom and formed a small pool. Womb-like cult temple was used by the Thracians as divine mystery called Dionysiac orgies. For mountaineers climb to the cave is a wonderful walk in beauty and grandeur of nature, the height is a wonderful panorama.