Churches, also referred to as Hallowed Ground, are holy buildings where believers of God come to worship him. Due to its holiness, most demons can not enter or be on its grounds, but this weakness does not apply to much stronger demons, like the Princes of Hell. Nor can all but the strongest ghosts, however unlike demons, ghosts can enter holy ground, but doing so will destroy them. This weakness even applies if the building has been knocked down.

Due to their ability to repel demons, Samuel Colt had five frontier churches built on the points of his giant devil's trap, over the Devil's gate.