Beneath a portion of west-central Kentucky, in the United States, beneath the feet of visitors to Mammoth Cave National Park, is the park’s namesake, a vast warren of tunnels, caves, and caverns called the Mammoth Cave. With over 400 miles of known passageways and more being discovered, it is by far the longest cave system in the world, drawing in droves of visitors willing to take tours of its murky subterranean depths. Yet although it is certainly a geological wonder, the caves are also known for a spooky experiment once carried out here, which is at once a strange historical oddity and the source of tales of hauntings.
It all began with a man by the name of John Croghan, who was a physician living back in the 19th century, whose main area of study was finding a cure for tuberculosis. This was an era in which tuberculosis was a scourge, poorly understood, mysterious, and terrifying in equal measures, at the time also called various other names such as Pulmonary Consumption, Pthisis, Scrofula, and the White Plague. The bacterial lung condition during that era of incomplete medical knowledge was highly feared, to get it tantamount to a death sentence. At the time very little was known about how it spread, what exactly it did to the body, or how long one could expect to live if infected. There was no known treatment for it other than a healthy diet, rest, fresh air, and light exercise, which did little to alleviate the wasting away of the patients, and so there was a great push of resources aimed at trying to find ways to stop it and to separate those infected from the rest of the population. Dr. Croghan was very active in this endeavor, especially so since he also contracted the disease in 1839, further fueling his urgency to find a cure.
During Croghan’s research into tuberculosis treatments, he quite by chance stumbled across tales of the Mammoth Cave. It was said that the air and darkness of the cave had a sort of healing and preservative effect, with stories common of how nothing seemed to ever deteriorate down there, with even dead animals barely decomposing. Numerous workers at the cave’s saltpeter mines also claimed that they had miraculously been cured of physical ailments from being down in the cave, that they never got sick, or that the atmosphere there gave them increased strength and vigor. Croghan became fascinated by these wonderful stories, as well as convinced that the Mammoth Cave, for whatever reasons, had remarkable and mysterious curative properties, which gave him an idea. He surmised that if tuberculosis patients were to live down in the cave for an extended period of time, they might get better, if not be completely cured, and so his odd experiment began.
Croghan started by flat out purchasing the cave in 1839 for $10,000, which was quite the chunk of change back in the day, but he was from a very rich family. In addition to his hopes to conduct tours in the cave to fund his operation, his main order of business was to create a large health resort for victims of tuberculosis. To this end he began construction of 10 wooden cottages and two stone ones, which were situated about a half a mile into the eternal darkness of the cave. When this was completed, in 1842 Croghan began recruiting patients to live there, finding 15 people willing to live there indefinitely until their condition was cured. Although living in a cave did not seem to be a desirable way of life, you have to remember that these people were desperate, tuberculosis was considered an incurable terminal illness, and they had nothing to lose.
Although these patients had confidence in Dr. Croghan’s claims that their new home would cure them, living conditions certainly did leave a lot to be desired. Besides the never-ending gloom and complete lack of daylight throwing their body clocks off, the air was always uncomfortably cool, which was encouraged because it was thought that cool air was better for their condition. Meals were sparse, brought in by slaves, and there wasn’t much to do down there other than read books or hold sermons to pass the time in the eternal night. Occasionally they would light fires, and the smoke from the fires, as well as fumes from burning lamps, would make their coughing even worse.
Throughout it all tour groups would often pass through and spot the pale, gaunt patients lurking about in the gloom like ghouls, the cacophony of their coughing hauntingly echoing through the dark even when they were not visible. There were many reports from visitors who were startled by the gaunt, spectral appearance of the patients. One slave server said they looked “more like a company of skeletons than anything else,” and a tour visitor once described it as “a bizarre scene. Pale, spectral figures in dressing-gowns moved weakly along the passageway, slipping in and out of shadowed huts, the silence of the cave broken by hollow coughing and muttered conversations.” Some descriptions were even more spectacular still, such as one visitor who said, “When they reached the light again, it was discovered that all their eyes were perfectly black, no matter what their original color had been.”
Over the next five months these patients would eke out an existence in the dank isolation, and although a few of them reported feeling better and healthier, it seems that these were the exceptions. During those five months, one left when he could not bear living in a cave anymore, and five died of their condition, after which the experiment was ended, considered a failure. Croghan would continue to use the cave for tours using slave guides, while also becoming instrumental in developing it as a tourist attraction and mapping large portions of it, but he never did reopen his cave colony, despite still holding hope that it could work. Indeed, he would never officially publish the results of his bizarre experiment, and avoided speaking publically about it. However, for many it was not considered a complete failure. Many in the medical field were inspired by Croghan’s ideas, and the idea that cave air could treat tuberculosis continued for some time, with many tuberculosis sanatoriums emulating these conditions for their own treatment regiments. Dr. Croghan would finally succumb to the disease in 1849, and tuberculosis would eventually be cured with the development of the BCG vaccine in 1921 and the discovery of the antibiotic Streptomycin in 1943.
To this day, the two stone huts that were built for Croghan’s subterranean colony still stand in Mammoth cave, and can be seen by taking the 3-hour Mammoth Cave Violet City tour. The huts have also managed to attract various rumors of ghosts and hauntings. Visitors have reported hearing ghostly hacking and coughing coming from the darkness near the huts, as well as seeing spectral pale apparitions. Ghostly activity has also been reported from a place called “Corpse Rock,” where the bodies of Croghan’s dead patients were kept until they could be properly buried. There are also reports of seeing the ghosts of slave guides who died in the cave, as well as numerous reports of people feeling unseen hands poke and prod them. It certainly seems to be the sort of place where one would think negative forces from the past would linger, and whether it is really haunted or not, the story of John Croghan and his subterranean colony of terminal patients is certainly a weird and perplexing historical oddity.