A former sanatorium saw barbaric experiments on its thousands of patients in a bid to cure their tuberculosis.
Waverly Hills Sanatorium in Kentucky opened its doors in 1910 in an attempt to contain an outbreak of tuberculosis - known then as the "White Plague" - in Jefferson County and was thought of as one of the most advanced hospitals in the country.
The site closed in 1961 and is today believed to be one of the country's most haunted locations.
More than 50,000 patients are thought to have died there, according to some estimates - although more conservative numbers suggest it may have been as low as 6,000.
The derelict and graffitied site has become a favourite among ghost hunters and tours who search the halls and structures that remain largely as they when it was in use.
A particular macabre feature of interest is the 500 feet-long 'body chute' that the dead were dumped down so the sanatorium's live residents would not see how many people were dying.
With so many agonising deaths on its grounds, Waverly Hills' reputation as a haunted location has only grown over the years.
One of the site's most well-known ghosts is a playful boy called Timmy who is said to interact with visitors.
All they have to do it roll a ball down one of the long corridors and he will creepily roll it back.
Other ghostly residents include a nurse who hung herself in room 502, where other staff allegedly jumped out of the window to their death and which is the location of heavy paranormal activity.
While a man dressed in white hangs around the kitchen where food can sometimes be smelt in the air.
Although the 400-bed sanitorium was designed to help patients, many of them were subject to seemingly cruel experiments.
One included exposing them to extreme weather and stories tell of patients sat freezing in chairs in front of huge open windows while covered in snow.
The most notorious experiments involved implanting balloons in a patient's lungs, which were then filled with air, or even removing a few ribs in the belief that it would allow more oxygen into the lungs.
These attempts at curing patients often did more damage than good and many did not survive the blood-stained surgery.
Tuberculosis was in decline by the 1940s, largely thanks to developments in medicine, and Waverly Hills closed its doors f in 1961.
However, it reopened as a hospital for the elderly and mentally handicapped the following year and stayed open for another 20 years - despite reports of patient mistreatment - before being abandoned as a haunting reminder of a diseased past.
