What approximate distance in kilometers did the deepest hole drilled reach?

The deepest hole ever drilled by humans is known as the Kola Superdeep Borehole, which was initiated in 1970 in Russia. This borehole reached a depth of approximately 12 kilometers. This remarkable achievement in scientific drilling allowed researchers to study the Earth's crust, providing insights into geology and the conditions deep beneath the surface.

While 15 kilometers, 10 kilometers, and 8 kilometers are significant depths, they do not match the actual record of the Kola Superdeep Borehole. The choice of approximately 12 kilometers accurately reflects the depth achieved, making it the right answer in this context. Understanding the importance of this drilling project highlights both the technological advancements in drilling techniques and the scientific curiosity driving such exploratory endeavors.