American warfare 1690-1815 in popular culture, art, in miniature and in wargames, through Living History and in movies.
this is called a Bartizan, A bartizan or guerite ( garita) is an overhanging, wall-mounted turret projecting from the walls of medieval fortifications from the early 14th century up to the 16th century. Most frequently found at corners, they protected a warder and enabled him to see around him. Bartizans generally are furnished with oylets or arrow slits. The turret was usually supported by stepped masonry corbels and could be round or square.other forts with this feature, Castillo de San Cristóbal (Puerto Rico)and Castillo de San Marcos (St Augustine Florida
My article on the fort: http://www.ameriquefrancaise.org/en/article-675/Fort_de_Chartres_in_Illinois.html