In 1914, the spacious Mineral Springs Hotel opened its doors to overnight guests seeking its namesake mineral treatments. Though designed for relaxation, the hotel and spa became the unwitting host of homicides and suicides to mysterious, accidental deaths. These days, in its 100th year, the only people spending the night are attendees of Mineral Springs Haunted Tours' "Haunted Overnights," where brave souls camp out inside the hotel's basement pool, or other areas of the building. As the hours pass, they might detect signs of spirits such as the "Jasmine lady," who took a fatal tumble down the hotel's steps.

Those on the walking and overnight tours scour the hotel with ghost-hunting equipment at the ready before launching into a poolside séance and tarot card reading. Besides exploring the hotel, walking tours visit upwards of 10 other haunted Alton locations, including tunnels under the old Enos Sanitarium. In addition to leading paranormal treks, the Mineral Springs team of paranormal investigators teach the tricks of their trade to aspiring ghost hunters at its Paranormal Research Center, where there have been six documented ghost cases. For winter tours, the company even unveils its private collection of over 50 historically-accurate torture devices, whose origins span across the globe from ancient times to present.