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Highest altitude reached by a gun-fired projectile

Highest altitude reached by a gun-fired projectile
Who
High Altitude Research Project
What
180 kilometre(s)
Where
United States (Yuma,)
When
19 November 1966
The greatest altitude ever attained by a projectile fired from a gun was achieved by the HARP (High Altitude Research Project) gun, consisting of two barrels with a calibre of 42 cm (168 in) fused into a single elongated barrel 36.4 m (119 ft 5 in) long and weighing 150 tonnes, at Yuma, Arizona, USA. On 19 November 1966 an 84 kg (185 lb) projectile was fired to an altitude of 180 km (112 miles).