The Kola Superdeep Borehole

During the Cold War, the United States of America and the Soviet Union had a long line of weird competitions and races.

First man on the moon, most nuklear warheads and in the case of this article, who can dig the deepest hole, in the name of science.

The project was started in May 1970, and continued until funds dried up in 1995, after the collapse of the Soviet Union.

The drilling was active in periods. 1970-1983, 1984 and 1985-1992.