In architecture, a turret is a small tower that projects from the wall of a building, such as a medieval castle or baronial house. A building may have both towers and turrets; turrets might be smaller or higher but the difference is generally considered to be that a turret projects from the edge of the building, rather than continuing to the ground. The size of a turret is therefore limited by technology, since it puts extra stresses into the frame of the house. It would traditionally be supported by a corbel.

A turret might have a flat top with crenellations as in the picture, a pointed roof, or any other kind of top. It might contain a staircase if it projects higher than the building. However, a turret might not be any higher than the rest of the building; in this case it is part of a room, that can be simply walked into – see the turret of Chateau de Chaumont on this collection of turrets, which also illustrates a turret on a modern skyscraper.

Gun turrets

Since the technology of war has advanced there are now new types of turrets.

Such turrets are usually rotating armoured mounting weapons. These are installed on armoured fighting vehicles, warships, military aircraft or towers).

The most common use of the term turret is for the rotating cabin installed on a tank or ship equipped with a large calibre gun . In modern main battle tanks, the turret is manned by the tank-commander and the gunner and can rotate 360 degrees. It is armed with a large caliber gun (a cannon of 105 mm, 120 mm, 125 mm or higher) and has independent scopes systems and outer armour to protect the tank crew.

Rotating machine gun post on other vessels such as APCs, naval ships and B-17 "Flying Fortress" can also be called a turret. Some of those turrets are automatic and controlled from within the vessel and others are manned. Not all of those turrets have armoured protection.

Examples:

• Some APCs have a 30 mm gun turret for suppressing fire support.
• The IDF Nagmachon has a fixed pillbox turret, enabling the troops inside to shoot soft targets without being exposed to enemy's fire.
• The IDF Machbet has a turret armed with M61 Vulcan rotary cannon and a FIM-92 Stinger launcher.
• In World War II, battleships had 3 to 4 turrets armed with several 14 to 16 inch (356 to 406 mm) cannons.
• The legendary bomber, the B-17 Flying Fortress, had 5 turrets with heavy .50 cal (12.7 mm) machine guns in order to fend off attacks from enemy fighter aircraft.
• The Cold War Convair B-36 carried six remotely-operated, retractable turrets, plus two more at the nose and tail. Each turret had two 20 mm cannons, making the B-36 the most heavily-defended aircraft ever.

See also

• Armoured fighting vehicle
• tank
• battleship
• chassis
• APC
• machine gun
• fortification