长城词典·敌台又称空心敌台、敌楼，是蓟镇长城创建的一种楼台式军事建筑设施。多数修建在长城墙体上，有的独立于长城外侧或内侧。敌台多为方形或长方形，偶见圆形。边长多在8~10米之间，由下中上三部分组成。下部为条石垒砌的基座，一侧或两侧突出于城墙外；中部为砖砌空心楼体，用于驻守士兵、存放粮食和武器，楼体两侧多有箭窗，前后两面有箭窗和券门；上部多为平顶，台顶正中建有楼橹（又称铺房），供守城士兵遮风蔽雨。台顶四周筑垛口墙。也有的敌台，不筑楼橹，可燃放烽火。敌台间距数十至数百米不等。 Great Wall dictionary·WatchtowerWatchtower is also named Hollow Watchtower and Enemy-watching Tower. It is a military facility constructed on high building. Many Watchtowers are built attaching the body of the Wall，some stand independently on its interior or exterior side. It usually takes the shape of square or rectangle with few round ones. The length of its side is between 8-10 meters，consisting upper，middle and lower part. The lower part is made of strip stones （sett piling） with one or two sides sticking out the Wall；the middle part is built with bricks with a hollow heart，serving for station troops，storing grains and weapons. On both sides of the tower，there are windows for arrow-shooting. The top of it is a platform in which a Lulou （a high watch stand serving for offensive and defensive purpose） is built right in its middle to protect the garrisons from wind and rain. The platform top has crenels. Some watchtowers are not equipped with Lulou but with beacons.
