Fortress of Bourtange
This is a typical example of a fortress built according to the old system of Dutch fortification, built around a pentagonal bastion surrounded by two moats. The fort can only be reached by two narrow roads which lead to the market square via a maze of bridges and vallum walls. Ten streets radiate around the square towards the bastions and main perimeter wall. This radiating layout enabled troops to be quickly deployed while maintaining a good view of the whole settlement.