1894 Old County Jail
Green Cove Springs, Florida
A surprising number of violent criminals (including at least one ax murderer) ended up in this 16-cell, supposedly haunted jail. See a model of the gallows that hanged the jail's last capital punishment prisoner in 1915, a display of old crime guns, and a dummy in prison stripes hanging by his fingers outside one of the barred windows.
The town archivist's office is in the 1894 jail (it closed as a place of incarceration in 1972). She's heard footsteps when no one else was in the building, and has dozens of EVP (electronic voice phenomenon) files on her computer, recorded by ghost hunters who've spent the night in the jail, and who claim that the spirits are telling them to get out!
If you visit in daytime, and are interested in the historical displays, the ghosts apparently don't mind.