" There might some truth to this, since ghosts fade over time. There are few, if any, spirits that can be attributed to cavemen or ancient civilizations like Rome or Greece. In fact, it’s difficult to find any spirits that can be attributed to a living person more than five hundred years old. So why do they fade away? Could it be that the water in the building that they occupy is evaporating slowly and taking their memory with it? If this is true, then maybe bodies of water (rivers, lakes, or moats) are storing the residual energy of the living as well. We know that EMF increases around water, so with a dedicated study, we may be able to show that the top 500 most haunted places in the world are on or near a body of water and therefore have a relationship to paranormal activity. "

― Zak Bagans , Dark World: Into the Shadows with the Lead Investigator of The Ghost Adventures Crew