Before the hospital even opened its doors in 1902, it had already faced unusual challenges. The first building on the site was completed in 1897, and described as "a facsimile of a feudal castle." This building was never inhabited and was eventually torn down and replaced by the "cottage plan" of multiple buildings by 1902.

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The reason for the abandonment and demolition of the original structure is uncertain. Most sources cited a series of abandoned mine shafts beneath the property, undermining the structural integrity of the original castle-like building. However, a 1927 history of the Peoria State Hospital, held in the archives of the George A. Zeller Mental Health Center Professional Library, states that the reason the original building was never occupied was that it "was found to be wholly out of harmony with modern ideas for the care of the insane."

Whatever the reason for the change, the hospital opened under the new "cottage plan" in 1902, with 33 different buildings including a communal utility building, a power station, and housing for patients and staff. The new hospital opened under the administration of Dr. George A. Zeller. Dr. Zeller was considered a pioneer in mental health and the day-to-day running of a hospital. He was also the source of one of the most dramatic ghost stories in the hospital's long history.

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Among the innovations that Dr. Zeller brought to the hospital was a way to take care of unclaimed bodies. Patients who died in the care of a hospital and who had no family members to claim them had formed a bit of a problem for a number of asylums at the time. Dr. Zeller formed a burial corps made up of several staff members and a handful of patients who buried the unclaimed bodies in a small cemetery on the hospital grounds.

One member of this burial detail was a well-liked patient who everyone at the hospital simply called Old Book. In fact, Old Book was so well liked that when he eventually passed away, around 100 nurses and more than 300 spectators are said to have attended his funeral. These mourners then bore witness to a chilling sight: According to Dr. Zeller, writing about the occurrence in his 1937 memoir Befriending the Bereft, all those assembled mourners saw the apparition of Old Book appear next to the cemetery Elm while he was being buried.

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What's more: After Old Book's body was interred, the tree began to die, and every attempt to chop it down or burn it failed. The tree itself was said to wail and cry whenever it was cut or a fire was lit nearby. It is only one of the many eerie events that have been recorded at the Peoria State Hospital over the years, though it is difficult to imagine one more striking or which was observed by so many witnesses. 

In 1907, the hospital dropped the word "incurable" and became the Illinois General Hospital for the Insane. Then, in 1909, it traded all that in and become the Peoria State Hospital. At its peak, the hospital housed around 2,800 patients. When its closure was announced only 20 years later, that number had dropped to 600. Peoria State Hospital’s doors were officially shuttered in 1973.

Since its closure, most of the hospital's 63 buildings have been demolished or converted into industrial or commercial businesses. The Bowen Building, which once housed the hospital's administrative offices, is undergoing demolition, in spite of fundraising efforts by the Save the Bowen Foundation. 

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The cemetery still stands on the hospital grounds. Sometime after the burial of Old Book, the cemetery Elm was struck by lightning and finally removed. Yet rumors of sightings of Old Book—and the sounds of his sadness—persist till this day.

As for the actual gravesite of Old Book? For decades it remained without a headstone. Around 2010, however, one former hospital employee erected a memorial in honor of the former patient.

Featured photo: Wikimedia Commons; Additional photos: Destination America / YouTube; Alchetron