High up in the mountains of North Carolina, a mystery has gone unsolved for more than a century.

The strange phenomenon made its first headline in The Charlotte Observer 99 years ago, and some locals claim that sightings go farther back than the American Civil War.

They call them the Brown Mountain lights: glowing orbs that float and flicker on a wooded ridge in Burke County. Most sightings take place from faraway scenic outlooks circling the area, but some have reported seeing the lights up close and in person.

Burke County resident Steve Woody told the Associated Press that over 50 years ago, he and his father saw the lights nearby. They looked like orange orbs, floating 10 feet above the ground. It was just a unique situation, he said. It's just as vivid now as when I was 12 years old.

Explanations have been attempted. In the 1920s, he U.S. Geological Survey concluded that the lights were really just reflections of fires, train headlights and automobiles. Others have suggested that this is an example of ball lightning, a rare phenomenon that scientists have yet to fully explain, in which tennis ball-sized bundles of electricity seem to float through the air and then fizzle out.

Ed Phillips, for one, knows exactly what these mysterious lights are: an opportunity. He's the tourism director for Burke County, and he's already held on a sold-out symposium on the phenomenon. More events, contests, expeditions and souvenirs are in the works. The Brown Mountain lights was something I really wanted to bring back to people's attention, he said to AP.

Sightings aren't all that common, but over the last decade several intrepid mystery seekers have been able to capture the Brown Mountain lights on film. Below are three independent shots of the strange phenomenon: a far-off version filmed from an outlook in Linville, a night vision video captured during the making of a documentary, and footage from 2000 that many claim was the very first time the phenomenon has been captured on film.