Most of us don't see ghosts until they show up at our door, saying "trick or treat" on Halloween.
But in Jackson, in the state's first prison, tour guides and ghost hunters say they see them year round.
Some say Michigan's first state prison is haunted.
It opened in 1838 and closed in 1934. During its nearly century-long run, hundreds died. Many passed to disease, others to suicide, and a few people today have what they say is proof some prisoners and wardens, haunt their former home.
What was once the world's largest walled prison spans 20 acres with stone and granite walls standing 25 feet high.
While the physical structure is massive, its population helped give it the title of world's largest.
At 3,840 prisoners at its max, overcrowded, capacity, Michigan's first state prison was big enough inside to fit one-third the population of Jackson.
Prisoners lived under the harshest of conditions.
"No electricity, no heat, no plumbing," said Judy Gail Krasnow, founder and director of Jackson Historic Prison Tours.
One watchman wrote a book of his experience.
Steve Rudolph, the other prison tour guide, recounted the watchman's experience in the wintertime.
"All he could hear was 300 pairs of jaws chattering in the cold. He said people in the upper sections would go mildly insane."
Hundreds died from disease.
"Absolutely no ventilation, yes, dysentery, syphilis, tuberculosis were rampant in the prison, there was many a death you can be sure," said Krasnow.
But some died a slow death by punsishment.
"They would chain them at the wrists with with an iron hook hung through, and you'd be hoisted up with your feet four to five inches off the ground, and left that way anywhere from 5 to 72 hours," said Krasnow.
Others committed suicide, some in the basement.
"This is solitary confinement," said Rudolph. "No light, no sewer...they just got bread and water."
Each prisoner entered the prison under the Code of Silence.
"You would be under the Code of Silence for five years unless a guard talked to you," said Rudolph.
You weren't allowed to utter one single word. The prisoners knew how to how to be silent better than anyone. And now, some people believe, some prisoners' have found their voice, from beyond the grave.
"We are about to enter the tunnels. You have to bend down this little stairway," said Krasnow.
In the tunnel, prisoners walked to work at the Jackson Carriage and Wagon Company.
"People have been down here, have heard banging on pipes, have heard screams. We've gotten EVPS, electronic voice projections of people saying 'help, out here,'" she said.
Paranormal investigators with Haunted Travels of Michigan are a few of the people who have gathered sound and pictures.
One voice on their recording says "It's me."
They, along with Krasnow, have spent countless hours down in the tunnels.
"And they said this place is hot," said Krasnow.
But the voices often come with a face and a shape. They're called orbs.
Krasnow says she felt one's presence.
"I felt like I was being pushed over," she said.
(The paranormal investigator) "He got a shot, and it was three, pure, beautiful orbs in exactly the position I had felt," she said. "And he pulled me aside. And dust floats, but these orbs dropped, in their positions, and went scurring down this tunnel."
Krasnow says at least 50 clear ghosts and others as shadows have been reported.
Not just in the tunnels, but in solitary, prison hallways, the mess hall, and her apartment on the prison grounds.
They've seen doors open and close, and have heard footsteps at night.
But it's the voices, another one said "Killed Someone," that convince some, prisoners who never made it past the walls, or their code of silence, are finally speaking out.
Krasnow says ghosts have also been sighted at the Southern Michigan State Prison, which opened after the old Jackson State Prison closed.
You can see a closed cell block in the current prison on this tour.
Tours end November 3rd. Click the link below for more information:
Jackson Historic Prison Tours