What is the deepest man-made hole on Earth?

The deepest man-made hole on Earth is the Kola Superdeep Borehole, located in Russia. It was drilled by the Soviet Union in the 1970s and 1980s and reached a depth of 7.5 miles (12 kilometers) in 1989.

The primary goal of the Kola Superdeep Borehole was to study the Earth's crust and better understand its composition and structure. The project was led by Soviet scientists and involved drilling through layers of rock and sediment using a series of drill bits and drilling fluids.

At its deepest point, the Kola Superdeep Borehole penetrated through the Earth's crust and into the upper mantle, which is the layer of hot, molten rock that lies beneath the crust. However, the project was eventually abandoned due to a number of technical and logistical challenges, including high temperatures and pressures at such depths and difficulties in drilling through hard rock.