About 2:30 a.m., public-safety officer Roy Surma was on patrol alone in the basement of Grey Towers, the rambling 1890s English-style castle that houses administrative offices and student rooms at Arcadia University in Glenside.

"Just as I adjusted my radio, something clamped on my wrist," he said, recalling the chilling grip he felt six years ago. "Of course, there was nothing around me. What it was, I have no idea."

Surma is one of many employees and students who tell of ghostly encounters at the three-story, 40-room mansion, built by a sugar magnate who wanted to make a societal splash.

Modeled after Alnwick Castle in England, where early Harry Potter movies were filmed, the 50,000-square-foot building is perfect for a haunting, with dark, dank, cobwebbed tunnels that run underneath it to other areas of the campus and are said to harbor ghosts.

Across the region, many colleges nurture their own ghost stories, handed down by generations - some based in fact, others in fiction. For some, the stories serve as nothing more than Halloween fun. To others, they seem very real.

At the University of Delaware, Elmo, a workman who died in the 1920s, is said to leave a "trail of chilled air" and make an "asthmatic breathing" noise in Mitchell Hall.

A benevolent ghost allegedly climbed into bed with a student at Rutgers University in New Brunswick, N.J.

And at Gwynedd-Mercy College's Assumption Hall in Gwynedd Valley, lights mysteriously turn back on at night, supposedly the work of a young woman who tripped in her wedding gown and fell down stairs to her death.

At Arcadia, some of the ghost stories emanate from the castle's basement, which leads to the 500 feet of tunnels that were built as utility conduits. Spray-painted on the entrance walls are an image of a dog and the word danger. Adding to their mystery, the tunnels have been off-limits.

As interest mounted, the college this month began offering tunnel tours to small groups of staff and students. Recently, staffers with flashlights led reporters through the at-times puddled, muddy passages, which dip and climb and are lined by pipes.

"When you're in the basement, you'll see things out of the corner of your eye, and you'll swear somebody just walked by," said John Hagerty, maintenance supervisor, who at one point had all the flashlights turned off in the tunnels to give his visitors a feel for the spookiness.

Students quickly learn the tunnels lore after arriving on the Arcadia campus.

Freshman Alex Knell, 18, was regaled with stories by an upperclassman until 1 a.m. the night he moved into the third floor of Grey Towers, which has a Victorian interior design and a medieval exterior.

"I was trying to go back to sleep, and I thought, greaaat," said Knell, of Pittsburgh.

Now, he loves it: "What other time are you going to get a chance to live in a $13 million castle?"

Arcadia, then called Beaver College, bought Grey Towers from the Harrison family in 1929 and began moving onto the property in 1935. Its entire campus was located there by 1962. The building houses the president's office, admissions, financial aid, and bedrooms for 44 students.

With a stately red carpeted staircase and ornately carved woodwork, it is popular among students. It includes a mirrored French Renaissance-style ballroom and "the red room" with painted angelic figures on the walls, where, lore has it, a murder took place.

One of the Harrison daughters also is said to have died young in a horse-riding accident, which may explain one story: Frequent spotting of a woman in 19th-century garb pacing in the woods, allegedly Mrs. Harrison, mourning her daughter's loss, said enrollment official Mark Lapreziosa, keeper of castle lore.

Fresh incidents give new life to the story. Christine Laughlin, 19, a freshman from Mount Carmel, Pa., said she had heard a voice singing "Ring Around the Rosie" in her room.

"Then you go and close the door, and you still hear it, and there's no volume change or anything," she said.

She's not shaken.

"Haunted or not, it's beautiful," she said of the spacious quarters. Laughlin will join other students tomorrow night in turning the building into a "Haunted Castle," an annual Halloween event.

When Shayna Devlin, 20, a junior from Glenside, lived in Grey Towers as a freshman, she said, her roommate saw a presence in a hooped skirt pace in front of their door.

"You kind of felt like you just weren't alone," she said.

Students also report feeling held back by a presence if they are running on the staircase. One of the Harrison children's friends allegedly fell and was hanged by her scarf there, Lapreziosa said.

Such campus ghost stories help freshmen adjust to living on their own for the first time, said Elizabeth Tucker, an English professor at Binghamton University, State University of New York. She is the author of the 2007 book Haunted Halls: Ghostlore of American College Campuses, which included the story of Rutgers' bed-visiting ghost.

Some campus ghost stories center on students who drank too much or took drugs or went swimming alone at night and met their demise, Tucker said. They remind students to behave safely, she said.

Higher education has proved fertile ground also because so many campuses are home to historic buildings and ancient artifacts.

"We have mummies in here. If there's going to be spirits -," said Brian McDevitt, director of building operations at the University of Pennsylvania Museum of Archaeology and Anthropology.

In December 2006, security cameras there captured an image that workers believed to be a ghostly presence. It reappeared frequently over the next two months in the museum's Etruscan corridor, McDevitt recalled.

"It looked like a man who had a long trench coat, a scarf, and a hat . . . floating," he said.

At Rutgers University-Camden, workers in the communications office have named their ghost Abigail.

Editorial media specialist Monica Buonincontri recalled her encounter last year in the former Victorian home, built in 1867, which houses the offices of 11 employees, including the chancellor. It was early one morning, and she spotted a woman she assumed was her assistant director. The woman was sitting at the assistant director's desk on the third floor, her back to the door. Her hair was in a bun, and she sported long, white, billowing sleeves.

But then Buonincontri went down to the first floor and saw the assistant director talking to someone else.

"I just stood there," she said, "and stared with my mouth open."

When she went back upstairs, the woman in the chair was gone. There was no way anyone else could have been there, she said.

Arcadia president Jerry M. Greiner said he doesn't believe in ghosts. But he couldn't help admitting that sometimes he felt a cool breeze swirling in his office at Grey Towers with no discernible source.

"I do find it unusual."

Surma, the public-safety officer who felt the ghostly grip, hasn't experienced other strange encounters.

"I guess he couldn't scare me," Surma said with a smile, "so he decided to move on to somebody else."