Properly built fortress constructed in time of peace to protect the area against future attack of the enemy. Since 1853,
forts in the Dutch Indies that were permanently armed by a garrison were classified into four categories.
Categories 1 and 2 were for forts to defend against a European enemy (only in Java). Categories 3 and 4
were considered suitable to defend against indigenous enemies.

Multi-angle fort with straight flanks with caponnières instead of bastions.