The Kola Superdeep Borehole was frozen in 1994. In 1983 it was already 12 km deep when they decided to stop the digging, and after another 262 meters were dug (it took a decade to “cover” this distance), the project was totally nixed. The official reason for it was a lack of financing, but insiders say that it was because of supernatural things going on inside the hole. The drilling technician assure journalists, that the project was fell-financed by the scientific foundations, and they actually stopped working because “demons started to get from under the ground”.

In 1983, the drill passed the 12,000 metres (39,370 ft) level and stopped drilling for about a year to celebrate the event.[3] This idle period may have contributed to a disappointing break-down on September 27 1984: after drilling 12,066 metres (39,587 ft) down, 5,000 metres (16,400 ft) of boring pipes tore off and were left in the earth.

The legend
The legend held that, after having drilled a hole nine miles deep, the Soviets hit a pocket of air. Intrigued by this unexpected discovery, they lowered an extremely heat tolerant microphone, along with other sensory equipment, into the well. The temperature deep within was a 2000 degrees Fahrenheit - heat from a chamber of fire from which screams of the damned could be heard. United States tabloids soon ran the story, and sound files - recordings of those alleged supplications from the damned - began appearing on various sites across the Internet.
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According to Rendalen, the "story" claimed not only that the cursed well was real, but that a bat-like apparition had risen out of it before blazing a trail across the Russian sky.

As it turns out, part of the legend is true: Soviet scientists had, in fact, drilled a hole almost eight miles deep in Kola (the Kola Superdeep Borehole), and found some interesting geological anomalies. Neither the Devil nor his minions made an appearance, however.[1] Temperatures reached 180 degrees Celsius (356 °F), making deeper drilling prohibitively expensive.