The Firehouse is a building type in Pharaoh.
Firehouses dispatch fire marshalls, who decrease the risk of outbreaks of fire. Fire is a devastating danger to cities if left unchecked, as they can quickly spread to neighboring buildings (even those that are normally immune to fire risk).
There are certain circumstances in which an area requires more than one firehouse. Buildings that are prone to catching fire tend to be smaller than those with a chance of collapse, and so they get less coverage when a fire marshall passes them than when an architect passes a collapse-prone building. In addition, certain buildings (such as schools and libraries increase their risk of burning down very quickly.
Firehouses are ironically prone to catching fire, a minor problem which should never surface as long as they're properly staffed. They have a slightly negative impact on desirability.