Walls and Gates
Many cities are surrounded by walls. A typical small city wall is a fortified stone wall 5 feet thick and 20 feet high. Such a wall is fairly smooth, requiring a DC 30 Climb check to scale. The walls are crenellated on one side to provide a low wall for the guards atop it, and there is just barely room for guards to walk along the top of the wall. A typical small city wall has AC 3, hardness 8, and 450 hp per 10-foot section.
A typical large city wall is 10 feet thick and 30 feet high, with crenellations on both sides for the guards on top of the wall. It is likewise smooth, requiring a DC 30 Climb check to scale. Such a wall has AC 3, hardness 8, and 720 hp per 10-foot section.
A typical metropolis wall is 15 feet thick and 40 feet tall. It has crenellations on both sides and often has a tunnel and small rooms running through its interior. Metropolis walls have AC 3, hardness 8, and 1,170 hp per 10- foot section.
Unlike smaller cities, metropolises often have interior walls as well as surrounding walls—either old walls that the city has outgrown, or walls dividing individual districts from each other. Sometimes these walls are as large and thick as the outer walls, but more often they have the characteristics of a large city’s or small city’s walls.
Watch Towers: Some city walls are adorned with watch towers set at irregular intervals. Few cities have enough guards to keep someone constantly stationed at every tower, unless the city is expecting attack from outside. The towers provide a superior view of the surrounding countryside as well as a point of defense against invaders.
Watch towers are typically 10 feet higher than the wall they adjoin, and their diameter is 5 times the thickness of the wall. Arrow slits line the outer sides of the upper stories of a tower, and the top is crenellated like the surrounding walls are. In a small tower (25 feet in diameter adjoining a 5-foot-thick wall), a simple ladder typically connect the tower’s stories and the roof. In a larger tower, stairs serve that purpose.
Heavy wooden doors, reinforced with iron and bearing good locks (Open Lock DC 30), block entry to a tower, unless the tower is in regular use. As a rule, the captain of the guard keeps the key to the tower secured on her person, and a second copy is in the city’s inner fortress or barracks.
Gates: A typical city gate is a gatehouse with two portcullises and murder holes above the space between them. In towns and some small cities, the primary entry is through iron double doors set into the city wall.
Gates are usually open during the day and locked or barred at night. Usually, one gate lets in travelers after sunset and is staffed by guards who will open it for someone who seems honest, presents proper papers, or offers a large enough bribe (depending on the city and the guards).