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The lakes, forests, mists and snow of the Kola Peninsula, deep in the Arctic Circle, can make this corner of Russia seem like a scene from a fairy tale. Yet amidst the natural beauty stand the ruins of an abandoned Soviet scientific research station. In the middle of the crumbling building is a heavy, rusty metal cap embedded in the concrete floor, secured by a ring of thick and equally rusty metal bolts.

According to some, this is the entrance to hell.

This is the Kola Superdeep Borehole, the deepest manmade hole on Earth and deepest artificial point on Earth. The 40,230ft-deep (12.2km) construction is so deep that locals swear you can hear the screams of souls tortured in 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.

The Soviets’ superdeep borehole isn’t alone. During the Cold War, there was a race by the superpowers to drill as deep as possible into the Earth’s crust – and even to reach the mantle of the planet itself.

Now the Japanese want to have a go.

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“It was in the time of the Iron Curtain when the drilling was started,” says Uli Harms of the International Continental Scientific Drilling Program, who as a young scientist worked on the German rival to the Kola borehole. “And there was certainly competition between us. One of the main motivations was that the Russians were simply not really open with their data.

“When the Russians started to drill they claimed they had found free water – and that was simply not believed by most scientists. There used to be common understanding among Western scientists that the crust was so dense 5km down that water could not permeate through it.”

“The ultimate goal of the [new] project is to get actual living samples of the mantle as it exists right now,” says Sean Toczko, programme manager for the Japan Agency for Marine-Earth Science. “In places like Oman you can find mantle close to the surface, but that’s mantle as it was millions of years ago.