On 20 February 1943, in Mexico, a farmer watched the ground of his cornfield crack open and start smoking. Within a year, Parícutin had grown more than 300 m tall; it stayed active until 1952, burying two villages under lava. It is one of the very few volcanoes whose birth geologists could follow from start to finish.
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.