| Structures
Basic Fortifications - When there isn't much time, effective fortifications can be built into the landscape.
Wall - Sometimes a wall can provide defense or slow the enemy's advance.
Dam - A river can be diverted or backed up for various reasons.
Bridge - Sometimes a bridge is necessary for traversing water or another geologic feature.
Watchtower - A tall structure built for scouting purposes.
Guard Tower - A tall structure built for defenders with ranged weapons.
Fortress - A large defensive structure.
Keep - A large structure that can be used as a base of operations in the wilderness or at the center of a small town.
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