Back before Edge City rose up to the sky, the old city laid their dead to rest underground in the Catacombs. They are long forgotten now, buried beneath centuries of infrastructure. Few remember they exist. Mother Superior and the Nightstalkers commonly use them for moving around the city. The tunnels are unlit and labyrinthine, with many dead ends and collapsed branches. Also common are neigh invisible dropoffs into subterranian caves. Mother Superior seems to have a comprehensive map for transit, all others beware. Getting lost can be a death sentence.