In fortification architecture, a terreplein or terre-plein is the top, platform, or horizontal surface of a rampart, on which cannon are placed,Webster's International Dictionary of the English Language, Vol 2, 1895 protected by a parapet.Griffith, Paddy (2006), The Vauban Fortifications of France, Osprey Publishing, (p. 63) In Martello towers, the roof or terreplein was sometimes surmounted with one or two cannon mounted on a gun platform with a central pivot, that enabled the guns to traverse up to 360 degrees.Clements, Bill (2011), Martello Towers Worldwide, Pen & Sword Military, (pp. 37-38)
In civil engineering works, a terreplein is an embankment of earth with a broad level top, which is sometimes excavated to form a continuation of an elevated canal across a valley.
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