Fortress, Schans and Battery

Forts, ramps and batteries are self-contained fortifications on all sides, with a four-, five- or hexagonal head shape. Construction often happened as part of a defensive line or theorem. A Schans is a small type of fortress with usually a supporting function in a line. The name battery was also used for this purpose. Common in forts, ramps and batteries is the application of ramparts and canals.