In theory, ghosts or spirits that remain here could be in anyplace at any time. It is estimated that there are seven ghosts for every living person on this Earth.
Ghosts will roam near their moment of death, or near the place of their burial. They can be found in the homes or residences where they lived or worked. Even long after the old home they lived in is torn down, spirits can linger on the site, looking for their home. So with this in mind, here are a few places that ghosts can be found:
1. Hospitals These places are always associated with death for spirits, although there was a report that a ghost was seen to be at peace in a hospital watching over the maternity ward.
2. Sanitariums, or old institutions Places where the human body experienced pain or death. Most notably, Waverly Hills Sanitorium, in Louisville, KY. One of the most haunted locations in the world.
3. Churches Ghosts will find a way back to their place of worship. The spirit could still be looking for guidance or resolution. Some of the most famous ghost photos of all time are of spirits in a church.
4. Schools Unknown thinking here, but possibly the ground the school is built on may still be haunted. I know of several instances where schools have had child ghosts in them though.
5. Cemeteries or Graveyards These places are most common for haunted locations. Recently departed spirits may find themselves here, very unaware of their surroundings. I have literally heard a ghost in a graveyard say "where am I ".
6. Battlefields Places of multiple death, or mass burial sites. Theses places have many souls wanting to reach out and communicate. Gettysburg, PA is known as the most haunted battleground in the world, and also one of the most haunted places on Earth.
7. Playhouses or Theaters For some reason those who acted in real life love their stage so much they will never leave it, even after death. I find this oddly understandable. It is said that Ford's Theater, in Washington, DC, where President Lincoln was assassinated, is still haunted.