Minnesota is host to a number of unsettling places that give off an eerie vibe to all who pass through them. We have haunted hotels, restaurants, and roads. But no place is more famously spooky than Duluth's Glensheen Mansion. Rumors have surrounded this home for decades, but tours of the mansion famously leave out any mention of the murders - or any potential hauntings. Still, the question remains: is the Congdon Estate haunted? And if so, by whom? Read on to learn the details of this famous Minnesota ghost story.

The strange tale of the Congdon family started in 1977, when Elisabeth Congdon was found murdered in the family home.

Elisabeth had been suffocated. She was found in her older sister Helena's bedroom. Elisabeth's nurse, Velma Pietela, was also found murdered.

Jewelry and other items found missing after the murders were later worn by Elizabeth's adopted daughter, Marjorie.

Many speculated - and still do - that Marjorie was the murderer. However, there was not enough evidence to convict her. The police let her go shortly after her arrest. Years later, Marjorie's second husband, Roger Caldwell, pled guilty to the murders in exchange for a lesser sentence. In his 1988 suicide note, Caldwell claimed his innocence.

Ever since, there have been reports of a ghost or two haunting the Glensheen Mansion.

Of course, the claims can't be verified. But there have been some interesting sightings.

Guests and passersby report seeing apparitions of two women standing in an upstairs window.

The window most often cited is the one belonging to the bedroom where the murders took place.

A black, shadowy figure has been seen in the basement.

Could it be a ghost? Or is this story just the product of someone's imagination?

Beyond these spooky sights, other signs of a haunting have been discovered.

For example, lights in the sprawling estate have been said to flick on and off on their own. Some have observed objects moving on their own.

Even stranger, an otherworldly mist has been reported in the library.

Some believe this is Elisabeth visiting her favorite part of the home.

We may never know the truth about the Congdon murders - or about the chilling ghost story that has sprouted up along with it.

The murder at the Glensheen Mansion remains one of Minnesota's most well-known mysteries. Because of the notoriety of the crime, it makes sense that a few other rumors cropped up along with it. Is it a real haunting, or is it just an urban legend? You may have to visit for yourself to find out.

Have you ever visited Glensheen? What did you think? Let us know your thoughts in the comments below.