Flèche (fortification)
A flèche is an outwork consisting of two converging faces with a parapet and an open gorge, forming an arrowhead shape facing the enemy.
The flèche is similar in plan to other defensive works like the ravelin or demi-lune, but smaller and built in front of the glacis. It was thus part of the outworks of a fortress. It was usually placed in front of the point of a bastion in order to create an additional level of fire.Literature
