Begun in 1970, the Kola Superdeep Borehole in Russia's far northwest reached 12,262 m in 1989. At the bottom the rock was hotter than 180 °C, and drilling had to stop. Yet this record covers only about 0.2% of the way to Earth's centre, and barely a third of the thickness of the continental crust at that spot.
On 27 August 1883, the eruption of the Indonesian volcano Krakatoa was heard as far away as Rodrigues Island, nearly 4,800 km away. Its pressure wave was picked up by barometers worldwide and circled the globe several times. The tsunamis that followed killed more than 36,000 people.
The deepest known point in the ocean, Challenger Deep, lies roughly 10,900 m below the Pacific surface. Drop Everest in and its summit would still sit about 2 km underwater. Down there, the pressure is more than 1,000 times what you feel at sea level, roughly a tonne pressing on every square centimetre.