From the end of the 1980s a strange phenomenon is happening in some Russian forests. People find strange, deep holes.
They appear in the dense forest, in the places you can’t get on the car or truck to bring any device to drill the ground. There is not any soil that should be taken from such deep holes is found.
On these pictures people go down to one of such holes but it just finishes with nothing. There are no reasonable ideas on how these holes appear and what they are being used for.