There are lots of underground resources in the Sakha Republic of the Russian Federation.
The most famous of these is the diamond mine called Mir Mine.
Looking at this picture, noticed that there is a similar place in Japan.
Do you know the caldera of Mt.Aso, Kumamoto?
This large natural depression due to the volcanic activity, that named Spanish-derived “caldera”, is the largest in the world.
It’s interesting to compare it with the artificial depression after mining.
Both natural and artificial have a majestic charm.
What do you think about it?