The Alps were born from a collision between Europe and a fragment linked to the African plate, the Adriatic microplate. During the crash, rocks from the African side were thrust over European ones. On the Matterhorn, the lower layers come from an ancient ocean and the European margin, but the famous summit pyramid is made of Adriatic, and hence 'African', gneiss.
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.