Parked in the middle of Centralia is perhaps the world's most useless fire truck.

The shiny, lime-green machine waits in a municipal building, ready to go. But the fire killing this Pennsylvania town is underground and nothing except time ? maybe a century or two ? will put it out.

That is the bizarre fate of Centralia, where a vast, subterranean coal fire ignited in an accident almost 50 years ago, gradually turning the settlement, about two hours drive from Philadelphia, into a ghost town.

Of the original population of around 1000, less than a dozen people remain, refusing to obey government orders to leave their homes.

Fading signs still mark Plum Street, or Apple, or Grape. There are telephone poles, street lamps, and graveyards ? four of them.

But there are almost no homes. Bare grass lines the crumbling sidewalks. Sometimes a few steps ending in thin air betray where a house stood before being torn down.

"I just don't know if there's such a thing as Centralia anymore," says Rich Polyniak, an employee with a local water company that continues to maintain the barely used infrastructure.

The fire smoulders underground, eating its way through one of many coal seams riddling the surrounding hills, a long-time mining area.

A secretive, bizarre town

Although the flames are never seen, they are felt.

Sulphuric smoke puffs up near a cemetery overlooking the town and on a freezing winter day patches of ground there are coffee-cup warm.

A little further, down a barricaded four-lane stretch of the old Highway 61, smoke pours from an enormous, crocodile-shaped crack in the tarmac.

Graffiti scrawled over the hardtop completes the end-of-the-world atmosphere.

"Man can U make anything that nature can't destroy," someone has written.

Surviving snippets of life in Centralia can seem as strange as the wider destruction.

Next to the immaculate fire engine, its doors emblazoned "Centralia Fire Co No 1," stands a police station, unmanned during a weekday visit. "Keep Centralia on the map," says a torn sticker on the door.

Outside one of the few surviving houses a boulder-sized lump of coal serves as base for a flagstaff. A miniature human skull sits underneath.

Outsiders ? particularly prying journalists ? are not especially welcome.

"If my mother knew I was talking to you, she'd shoot me," a man tells journalists at his door. "She's 83."

Page 2: Centralia's strange history