The deepest hole man has ever dug
RussiaThe Kola super well is the deepest man-made hole on the planet created by the Soviet Union with a depth of 12,263m.

Well is blocked in Kola in 2012. Photo: wikimedia
The record hole is located on the Kola Peninsula in northwestern Russia, not far from the Russian-Norwegian border. The pit itself is essentially a series of pits that branch off from the central pit. Among them, the deepest hole called SG-3 reaches 12,263 m deep in the heart of the Earth. Despite being so deep, the diameter of the well is only about 23 cm, no wider than a plate, according to IFL Science.
For comparison, the depth of the well is equal to the height of Mount Everest and Mount Fuji stacked together. It also surpasses the deepest point in the ocean, the Mariana Trench in the western Pacific Ocean, at a depth of 11,034 meters below sea level.
The Americans also entered the race to dig a hole of record depth. In the early 1960s, the United States carried out the Mohole Project to drill into the Earth’s crust and collect samples at the crustal-mantle boundary. Engineers plan to do this by drilling into the seabed from a ship near a volcanic island in Mexico’s Pacific Ocean. Unfortunately, the project failed and was eventually terminated after facing opposition from the scientific community, mismanagement, and funding issues.
In Russia, things are calmer. Drilling began on May 24, 1970, and continued until 1992, shortly after the collapse of the Soviet Union. Political turmoil and lack of funding put an end to this ambitious project. According to BBC Future, drilling stops when the temperature downhole rises to 180 degrees Celsius, much higher than the model predicted.
Currently, the drilling area is abandoned, only a dilapidated building remains, and the pipeline is bolted to the ground. Although the area was left desolate, in 2008 Russia announced plans to destroy the well. Some comments speculated that the shaft was partially blocked with concrete.
However, at its height, the project provided much new scientific data. First, the Kola super-deep well reveals invaluable information about the geology of the Earth during its 1.4 billion-year history. Most notable are deep rock formations that are saturated with water, once thought to be impossible because they were sealed under impermeable rock. The researchers also discovered 14 fossilized microorganisms, along with deposits of gold, copper and nickel.
Phuong Hoa (According IFL Science)