Did you know the deepest man'-made hole dug could only reach till one-third of the Earth's crust?
Kola Superdeep Borehole or Kol'skaya Sverkhglubokaya Skvazhina is the deepest made-made hole on Earth in Russia. With a depth of 12,262 metres, it has been since 1989 the deepest artificial point on Earth.
In actuality, the Kola Superdeep Borehole consists of several holes branching from one central hole. The deepest hole is called “SG-3,” and though just nine inches in diameter, it extends down a staggering 7.5 miles. That’s roughly a third of the way through the Baltic continental crust.
According to some, this is the entrance to hell. It took the Soviets almost 20 years to drill this far, but the drill bit was still only about one-third of the way through the crust to the Earth’s mantle when the project came grinding to a halt in the chaos of post-Soviet Russia.