Why Was the Deepest Hole Dug?

The deepest hole by far is one on the Kola Peninsula in Russia near Murmansk, referred to as the "Kola well." It was drilled for research purposes beginning in 1970. After five years, the Kola well had reached 7km (about 23,000ft).

What is the purpose of Kola Superdeep Borehole?

Drilling the Kola Superdeep Borehole was, for the most part, purely science-driven. Soviet scientists wanted to learn more about our planet's outermost layer, called the crust, to understand how that crust has formed and how it evolved.

When was the deepest hole ever dug?

The project attempted to drill as deep as possible into the Earth's crust. Drilling began on 24 May 1970 using the Uralmash-4E, and later the Uralmash-15000 series drilling rig, and it became the deepest man-made hole in history in 1979.