Amazing Star-shaped Fort in the Netherlands

About 32 kilometers northeast of Emmen is Fort Bourtange, a star fort in the village of Bourtange, Groningen, Netherlands. This uniquely shaped fort was built during the Eighty Years War (1568-1648) to control the only road connecting Germany and the city of Groningen which was occupied by the Spaniards at the time. In 1851, the Fort was converted into a village which is now preserved as a historical museum. [images via here, here, here, here, here, here.]