earthworks

noun earthworks

• barricade — A barricade is a line of vehicles or other objects placed across a road or open space to stop people getting past, for example during street fighting or as a protest.
• citadel — In the past, a citadel was a strong building in or near a city, where people could shelter for safety.
• fortress — a large fortified place; a fort or group of forts, often including a town; citadel.
• reinforcement — the act of reinforcing.
• barrier — A barrier is something such as a rule, law, or policy that makes it difficult or impossible for something to happen or be achieved.