Ghosts and other strange legends surrounding Penn State always seem to resurface around this time of year. And for good reason: Halloween affords the time to think about the unexplainable.

So whether you are already versed in the ghosts of Penn State or if you are hearing them for the first time, enjoy this overview of "The Big Three" hauntings on campus.

Pattee Library

This ghost story is based on an actual occurrence in November of 1969 and is one of the more popular tales in Penn State folklore.

A graduate student named Betsy Aardsma was doing research for an English class in the stacks of Pattee Library when she was murdered. To this day, the case remains unsolved and the story goes that she still haunts the library.

Ryan Buell, director and founder of Penn State's Paranormal Research Society, said "people claim that they feel watched, [or have] been touched or assaulted."

As recently as 1998, The Daily Collegian reported that a young woman looking at satanic books in the stacks felt like she was grabbed. Buell said she had an odd sense that something was following her home that night. She woke up in the middle of the night and thought she was being strangled and was unable to scream for her roommate's help. The woman was fine but vowed to never set foot in the library again.

"People who work there say they feel odd presences and notice things get moved around," Buell said. "We've done a few informal investigations, but I don't believe that it's Betsy."

Buell has a theory that there is a strange "energy flux" created from all the people and events that have passed through the old building. And it doesn't help when people are afraid of being in the library.

Schwab Auditorium

The ghost legend of Schwab might include three spirits, but President George W. Atherton, who is buried next to the building is the most well-known.

The President Atherton ghost is reportedly friendly, and watches over thespians and occasionally moves curtains.

The Paranormal Society did an investigation of Schwab Auditorium in the Spring of 2002, which was also covered by The Daily Collegian.

"The only weird thing that happened there was in the girls' bathroom," Buell said. "One of the investigators said the lights went out on her."

Buell said he heard a chair move in the attic and saw scrape marks on the floor from where it slid, but it was nothing conclusive.

Old Botany Building

Old Botany is one of the oldest buildings still remaining on campus. It was built in 1909 and is located directly across the street from Schwab Auditorium.

"Legend has it that Frances [President Atherton's wife] watches Schwab Auditorium through Old Botany's eyelike dormers," said an article in The Penn Stater Magazine in 1998.

Karen Snare is one of the staff assistants in Old Botany and during her three years working there, she has experienced some strange encounters.

"I came to work one day and put the key in the door and they both flew open," Snare said, noting that only one of the doors opens. "You have to physically pull a chain and lift the bolt from the floor [to open the other door]."

Snare said when she entered the building a roll of carpeting that was in the trash can the day before had been moved in front of a doorway.

"I locked myself in the office," said Snare, who was the only one in the building. "I heard the front door open and footsteps go upstairs."

It wasn't until 10 minutes later that the first faculty member arrived and they both heard what sounded like books hitting the floor.

"We found the office that no one uses upstairs with the door open and the lights on," Snare said.

There have been other odd occurrences of printers not working and a fuse box with one of the fuses inexplicably turned off. One of the staff pictures taken in front of the building showed a man sitting in the window upstairs that no one knew.

"I don't go upstairs," Snare said. "And I never believed anything until that day."