Rook bastion

Bastion front of Svartholm represents so-called star-shaped fortress, ie, a vivid example of fortification architecture of the 17th century.
In the picture the so-called 'outgoing angle' of bastion, ie angle directed to the enemy is seen. It is easy to understand the basic principles of the bastion system of Vauban. Notice how this bastion faces flanks by fire from adjacent bastions. The enemy has nowhere to go.