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Mysterious duel -

In 1876, physician S.E. Solly received some letters from Alfred Schlesinger, who was private secretary to Denver & Rio Grande Railroad founder William Jackson Palmer (pictured). The letters said that he had gone to take part in a "fight" at the Lawson Ranch, and asked Solly to come find his body, in case he didn't return from the fight.

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Mysterious duel -

Solly eventually found Schlesinger shot dead. There was a line drawn on the ground, which indicated a duel. Schlesinger mentioned in the letters that he'd not reveal his adversary for two years, if he lived. The identity of his murderer remains unknown.

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Servant Girl Annihilator -

The Servant Girl Annihilator, also known as the Austin Axe Murderer and the Midnight Assassin, was a serial killer who operated in Austin, Texas, between 1884 and 1885.

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Servant Girl Annihilator -

The serial killer got the nickname because most of his victims were servants. A man named Nathan Elgin was killed by the police, and it is suspected that he was the killer. Though the true identity of the Servant Girl Annihilator remains unconfirmed to this day.

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Treasure cabin -

In 1853, brothers James and Henry Wilson teamed up with a group of prospectors and went looking for gold around Jacksonville, Oregon. After one of the men was killed by a Native American, the brothers continued on their own.

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Treasure cabin -

They eventually built a cabin and dug a hole inside, where they hid the gold they found. Henry died and James escaped to California. Years later, he wrote to his cousin Ted Harper.

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Treasure cabin -

Harper and a poet named Sam Simpson went looking for the cabin 15 years later. They found burned ruins with Henry's body inside. Later that year another group of men went looking for the treasure. They didn't find it. But what they did discover was the deepest lake in America: Crater Lake.

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What happened to Etta Place? -

Etta Place was the companion of two famous American outlaws. One of them was Butch Cassidy. 

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What happened to Etta Place? -

And the other was Harry Longabaugh, better known as the Sundance Kid. Not much is known about Place, including who she really was, what she did, and where or why she disappeared.

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Bigfoot -

Bigfoot sightings date back a long time, including back in the Old West, with numerous newspapers reporting the existence of "giant wild men" and "wood apes."

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Bigfoot -

But there was a peculiar difference back then: Bigfoot stank! So much so that the creature was known as "Bad Smelling Tree Man."

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A Spanish ship in the desert -

Sightings of a Spanish ship stranded in the California desert were subject to much speculation and theories. Of course, this included the possibility of the existence of treasure.

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A Spanish ship in the desert -

In 1870, explorer Albert Evans claimed to have found "the wreck of a gallant ship." And so did Charley Clusker, later that year.

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A Spanish ship in the desert -

But despite the numerous sightings and testimonials over the years, the Spanish ship is deemed folklore. Is it really though?

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Belle Starr's murderer -

The infamous American outlaw Belle Starr was fatally shot in 1889 in Oklahoma.

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Belle Starr's murderer -

Starr did hang out with a lot of bad guys, and the identity of the killer remains unknown to this day. As for suspects, there's her husband Jim July Starr, a neighbor named Watson, and even Belle's son, Ed.

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The disappearance of Albert and Henry Fountain -

Army Lieutenant and attorney Albert Fountain is best known for being the trial lawyer for Billy the Kid (and losing his case). Years later, after receiving a threatening note at the end of a trial in Lincoln, New Mexico, Albert and his son, Henry, disappeared.

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The disappearance of Albert and Henry Fountain -

Fountain's wagon was eventually found, with traces of blood and bullet shells. Outlaw Sam Ketchum claimed that it was him and his brother, Tom "Black Jack" Ketchum (pictured), who killed the Fountains. Though his story didn't add up, so this murder remains a mystery to this day.

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Tom "Black Jack" Ketchum's loot -

Tom "Black Jack" Ketchum might not have killed the Fountains, but he did commit plenty of crimes, culminating with him being hanged in 1901.

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Tom "Black Jack" Ketchum's loot -

Legend has it that Black Jack hid a large treasure in Wild Cat Canyon in the Chiricahua Mountains of Arizona. Author William Ascarza even claims that the outlaw hid it in a cave known as "Room Forty Four." Tom "Black Jack" Ketchum's loot remains unfound to this day.

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The murders of madam May Prescott and her husband -

In 1916, the bodies of madam May Prescott and her husband, Fred, were found at their home in Flagstaff, Arizona. The murders were particularly gruesome, with both having their throats slashed and bullet wounds found on their bodies.

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The murders of madam May Prescott and her husband -

A note apparently left by Fred said that he killed his wife and then himself, but things just didn't add up. Given the lack of evidence, the jury found they died of "knife and gunshot wounds caused by the hands of unknown party or parties." It goes without saying that their murder remains a mystery.

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The disappearance of Pearl Hart -

The infamous Canadian-born Pearl Hart is one of the most famous female outlaws of the American Old West.

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The disappearance of Pearl Hart -

Pearl Hart became known, not only for her crimes, but also for dressing like a man. She was eventually arrested, but in 1902 received a pardon from Arizona Territorial Governor Alexander Brodie. Hart had reportedly become pregnant while in prison.

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The disappearance of Pearl Hart -

Pearl Hart was arrested multiple times afterwards. The last reported sighting of her was in 1924, in Florence, Arizona, after which Hart disappeared. No one really knows that happened to her, other than rumors that she lived a quiet life and died in 1955.

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Catherine "Miss Kate" Arnold's ashes -

The Sheridan Inn in Sheridan, Wyoming, opened for business in 1893. Showman "Buffalo Bill" Cody eventually bough the Inn a year later, after which he hired Catherine "Miss Kate" Arnold.

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Catherine "Miss Kate" Arnold's ashes -

Arnold worked at the Inn until she died in 1968. She requested her ashes to be placed in the wall of her room. Her wish was granted, but no one knows where exactly in the wall her ashes are. It's room 306, in case you want to book a night there!

Sources: (Grunge) 

See also: Draw! Notorious Wild West gunfights

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