This is hell door. World's deepest pit | Deepest Holes on Earth

The Kola Superdeep Borehole is the aftereffect of a logical penetrating undertaking of the Soviet Union in the Pechengsky District, on the Kola Peninsula. The task endeavored to bore as profound as conceivable into the Earth's outside. Boring started on 24 May 1970 utilizing the Uralmash-4E, and later the Uralmash-15000 arrangement boring apparatus. Boreholes were bored by fanning from a focal gap. The most profound, SG-3, achieved 12,262 meters (40,230 ft) in 1989 and still is the most profound counterfeit point on Earth.