The longest-range gun ever built was used by Germany in the final months of World War I. It fired a 100kg (220 lb) projectile to a range of 122 kilometres (75 miles). Its speed when it left the muzzle was 1500 metres (5000 feet) per second and it reached a maximum height of around 40 kilometres (25 miles) above the surface of the earth. It travelled around 6 times faster and 4 times higher than an average transatlantic passenger jet.
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