Cute Young Brunette Girl Posing At The Bastion Wall

Types
Solid bastions are those that are filled up entirely, and have the ground even with the height of the rampart, without any empty space towards the centre.
• Void or hollow bastions are those that have a rampart, or parapet, only around their flanks and faces, so that a void space is left towards the centre. The ground is so low, that if the rampart is taken, no retrenchment can be made in the centre, but what will lie under the fire of the besieged.