Water towers are large elevated structures which hold water. They are often located on hills or on rooftops so that gravity can help disperse their water to nearby buildings. Fictional water towers are often secret bases, missile silos, or other structures in disguise. If they do function as real water towers these structure are often empty in narratives, to the concern of nearby desert town residents. Conversely, full water towers may be at risk of collapse, also to the concern of nearby town residents. Empty water towers may be homes for vagrants and may have peepholes allowing people within to peer out.