This amazing place was found by one geologist from Irkutsk in summer 1949. It was a huge convex truncated cone with an upper horizontal section. Inside it had a funnel-shaped recess with a dome-shaped hill right in the middle.
The cone was rather big. Its height was about 10-15 meters from the upper side and 70-80 meters from the bottom side. The average diameter of the cone was about 130-150 meters. The depth of the inner circular ditch was about 8-10 meters. It was clear the geologist found a unique natural formation which didn't resemble any others. It was called the Patomsky crater after the river in the watershed of which it was located.