The sailors were the crew members of the Hunley, a Confederate submarine that went down in battle after sinking the Union ship Housatonic during the Civil War off the shore of Charleston in February 1864.

"I think it's a fascinating human story," said Brandy Culp of the Historic Charleston Foundation, who led the tour. "It's a story of great invention, hope and of course the tragedy that, in the end, these men gave their life for a cause they believed in."

The sunken submarine was raised from the ocean floor in 2000. In 2004 the recovered remains of the crew were buried with full military honors - the last Confederate funeral of the Civil War.

"Visitors to the graves knew that the Hunley had been brought up from the ocean bottom, and they're fascinated that marine science gave an identity to these people," Culp said. "They're all human stories."

The plot was among the highlights of "Tour de Graves," a special Halloween event at the cemetery, which dates to 1849. Although that tour focused on history, other Halloween cemetery tours across the country emphasize the mysterious and macabre.

OBSESSION WITH SPIRITUALISM

At Green-Wood Cemetery in Brooklyn, New York historian Jeff Richman said the stories are about "murder, mayhem, spirits and ghosts." For Halloween, he emphasizes the 19th-century obsession with spiritualism.

"Mary Todd Lincoln held séances in the White House," he said in a telephone interview. "People were convinced you could communicate with the dead. It was the fastest-growing religion of the 19th century."

People also seemed terrified of being buried alive, Richman said. Some caskets were outfitted with a string attached to the finger of the person in it and to a bell above ground.

"If the deceased heard dirt being thrown on the casket, the deceased was supposed to ring the bell to alert people that a big mistake was being made," he said.

At Charleston's Magnolia Cemetery, Culp pointed out Soldiers Ground, which holds the bones of hundreds of Civil War soldiers, and discussed 19th-century funerary architecture, ornamental ironwork, gravestone carving and its symbolism.

The tombstones of five children from the same family have carvings of tears and doves, but one carved stone cradle holds a bronze cast of the child's face, a common practice in the 1800s.

"When I was little, my mother used to take us to cemeteries. They were the first public parks," said Jan Keith, a tourist from Atlanta, Georgia, who stood near a pyramid-shaped mausoleum with stone carvings of upside-down torches that symbolize the extinguishing of life.

Winslow Hastie, the chief preservation officer at the Historic Charleston Foundation, said the rural cemetery movement in America, when graveyards moved out of churchyards and onto manicured acres of rural land, was sparked by Mount Auburn Cemetery, which was founded in 1831 near Boston.

"People would come to these places to picnic and ride around in their carriages," he said. "It was a leisurely thing. It wasn't morbid."

Eighteenth-century gravestones in the city of Charleston, which was founded in 1670, were morbid, with carvings of death's heads and skulls, Hastie said. In the 19th century they became more uplifting.

"It's about enlightenment, going to your just rewards," Hastie said.

Although cemetery officials say interest peaks around Halloween, some graveyards are year-round attractions. Angie Green, executive director of Save Our Cemeteries in New Orleans, said tourists flock to the above-ground tombs in her city throughout the year.

The non-profit organization offers 15 tours a week in St. Louis Cemetery No. 1 and Lafayette Cemetery No. 1, she said.

On All Saint's Day, November 1, New Orleans families visit and care for their family tombs. They wash the stones, bring flowers, have picnics and visit with cemetery neighbours they see once a year, Green said.

At St. Louis Cemetery No. 1, tourists often mark the grave of rumoured voodoo queen Marie Laveau, a 19th-century Creole hairdresser who lived in New Orleans, with three red X's, she said.

"They think it has some kind of voodoo connection," Green said. "People who are familiar with voodoo know that grave desecration is one the highest negatives you can do. It does not bring you any luck at all." (Editing by Patricia Reaney and Douglas Royalty)

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