I assumed that the Fortress beside the town of Gniew and Gniew itself, which appears as a walled town, would only be able to be entered or exited by the roads and gateways.
What a surprise when the Swedish garrison of the Fort jumped over the walls and attacked me, in the rear no less....

A Swedish Cavalry Regiment flew over the town wall into a Polish garrison unit's flank.....

N.B. The Swedes garrison the fort, the Poles the town which is adjacent the fort, at the start.
Is it possible to make roads the only way into these fortified areas ?
Notes by the scenario designers would also be helpful.
A great scenario by the way, thanks to the designer.