Dutch Fortress Museum

The Dutch Fortress Museum (Nederlands Vestingmuseum) is located in the city of Naarden, the Netherlands.

(During World War II, allied bombers returning to Great Britain from bombing missions used it as a marker.)

The fortifications themselves, including the bastions, date from the period 1575–1585, when King Philip II of Spain ordered them to be constructed.

A museum boat conducts tours on the easterly side of the moat from April to October.

Casemates built into the city walls near the narrow base of the arrow head contained guns that permitted the defenders to fire along the main moat.

Side view of the Nederlands Vestingmuseum. On the left are casemates. On the right are the powder tester (the pole), and the water postern.
Powder tester. There is a small mortar at the base in which one puts a measured sample of the powder one wishes to test. One then puts a cannonball on top of the powder. When the powder is ignited it throws the ball into the air. The mast is calibrated and the height the cannonball reaches indicates the quality of the powder.
Replica mortar