Stone, brick, earth, wood

Even a thin layer of water and mud were an effective obstacle, hindering enemy progress. Forcing the obstacle slowed down the attack and exposed the attackers to a prolonged effect of defenders’ fire. A water obstacle was much more effective when at the bottom of a water body or a moat there were sharp elements of a stockade or sharpened branches of trees. Contrary to appearances, a shallow muddy water obstacle was more effective than a deep one because boats with floating batteries could be used on the latter. Water obstacles were used from ancient to modern times. Great Pond is a good example of a regulated water obstacle.