Natural Phenomenon "The Stone Mushrooms" (aka "The Rock Mushroom") is disposed at an area of about 30 000 m2, 1 km north-east of village Beli Plast, near the road connecting towns of Haskovo and Kardjali. These are rock formations which for millions of years have been shaped by the water, sun and wind to gain its present shape of huge mushrooms.
The "Mushrooms" are about 2. 5 m high and have pink stumps and greenish hoods. The different colors of the stumps and hoods is result of their different mineral consistence.