Before we start this off, let me say that this particular horror story isn't for the faint of heart. If you aren't interested in having bad dreams tonight or fearing for you life every time you enter a hotel after reading this, then perhaps reading about The Oldest Restaurant In Illinois might better suit you. The man who most consider to be America's first serial killer, H.H. Holmes was a true living nightmare.

Warning: This post is a bit longer and more detailed than some of our regular pieces. Don't be intimidated by the text! You'll quickly get sucked into the story behind this real life murder house.

Before we tell you the horrors of The Murder Castle, you need to know what led up to this terrible piece of Chicago's history.

Born Herman Webster Mudgett, this heinous murderer would be known as several different names, most commonly H.H. Holmes as well as Doctor Henry Howard Holmes and the Doctor of Death. For the sake of making this all easier, we'll simply refer to him as Holmes from here on out.

Born in New Hampshire in 1861, Holmes as a child would be the target of bullying. At a young age, bullies once forced Holmes to enter a doctor's office and stand near skeletal remains. The bullies would then take the actual hand of the skeleton and reportedly placed it on his face, initially scaring him. Later the murderer would explain that this is where he first became infatuated with death and it sent him down his murderous slope.

As a teenager, Holmes would attend college and eventually end up at a school for medicine and surgery where he would begin to steal cadavers. Talk about creepy! His terrible tendencies would carry on as he would constantly find himself at the center of situations involving young boys that he had been seen with going missing or even mysteriously dying. Although looking back now it would appear clear as day that Holmes was the culprit of these murders and mysteries, he would always deny having any involvement in what had happened.

Pictured above: The 1893 Chicago World Fair.

Pictured below you can see the notorious Murder Castle, then known as the World's Fair Hotel.

After scamming his way through life, Holmes would begin to work at a pharmacy in Chicago. Eventually Holmes would buy the lot that is now known as the Murder Castle, where he would begin to construct a real-life murder house.

Like the perfect trap in a room full of rats, the hotel was only a few miles away from Jackson Park where the 1893 World's Columbian Exposition was held, a.k.a. Chicago's World Fair. The fair would bring in nearly 30 million visitors, all who had no idea such heinous crimes were taking place so close to this joyous event.

The hotel Holmes created was filled with windowless rooms, secret chutes, stairs that would lead to nowhere, numerous trap doors and so much more. Every room had a different means for murder, created in unthinkable ways. The twisted hotel owner even had alarm systems set up so he was able to tell whenever guests were walking around the murder house. To give you a visual, if any of you reading this watched American Horror Story's most recent season, you'll now understand where the inspiration for the creepy hotel came from.

So who did Holmes target? Generally the blonde women he hired to work at the hotel and the women he would date. But don't put anything past this man, he also had a history of frequently killing children as well as men. Next to his office in the hotel he had a soundproof room that he would let victims rot away in, leaving scratches all over the walls. The entire second floor was also said to be a complete nightmare. Secret chutes were used to dispose of bodies, sending them down to the basement where Holmes would dissect them and get rid of them in lime pits he had created in the floor. Seriously. This sounds like the plot to the next big hit movie, but sadly this actually happened.

Eventually once the fair was over Holmes would abandon the Murder Castle and run scams across the United States and Canada.

Besides murdering innocent people, Holmes enjoyed scamming people out of their money and would often make his victims take out life insurance policies for him to collect after their demise. Note to self: If a creepy man offers to pay for my life insurance policy but in turn asks that he be the beneficiary, politely decline and run for the hills.

In 1894 police would get word of the unspeakable crimes that took place at the Chicago hotel. After tracking down Holmes, he would be arrested in Boston and several investigations would begin to take place. Police quickly began to interview employees of the hotel, well...whatever ones they could find left. Specifically, the caretaker of the hotel stated to the police that he was never allowed to go to the second floor and was asked not to clean it. Red flag much? The police would spend several weeks going through the entire hotel, discovering various human and animal bones, piles of bloodied clothes and all of the torture chambers that were disguised as hotel rooms.

One of the most disturbing things discovered? A large stove with a woman's hair, jewelry and shoe was found. The ways of torture were endless for Holmes. As many remains and haunting things that were discovered here by police, there was only enough evidence to confirm nine deaths. Throughout his trail and time spent in jail, Holmes would confess to nearly thirty murders. While oddly enough some of the people he claimed to have murdered were people who were still alive, the evidence lets us speculate the he could have killed up to two hundred people.

In 1896 Holmes would be hanged, but not before making claims that he was possessed by Satan and that his face was changing, resembling the devil. In an even stranger twist, Holmes' great-great-great grandson would come out with a book in 2011 claiming that the madness of his ancestor was downplayed and that he was actually also Jack the Ripper. While there is no physical evidence that seems to support this theory, those who speculate point out that it could actually be possible. The victims of both murderers were the same and it was possible timing-wise that Holmes could have been in England. How insane.

Over the years, arsonists would attempt to burn down the hotel in 1895, only to be completely demolished in 1938. Another creepy factor? The caretaker who spoke of the second floor to the police, would later commit suicide in 1914, leaving behind a note that said "I couldn't sleep."

Did you realize this murder story was actually true? I'm still shaking in my boots. If you're looking to keep the hairs on the back of your neck raised, try reading about this Haunted Road In Illinois That Will Give You Nightmares.