Centralia, a Ghost Town on Fire Since 1962

"In 1962, a landfill site in Centralia, Pennsylvania was set on fire. The rubbish was located in the pit of an abandoned strip mine, and although it was believed to have been extinguished at the time, the fire actually remained burning in the lower depths and eventually spread to an eight-mile seam of coal, where it has now been burning for 46 years.

As you read this post the underground fire continues to burn, and it is now estimated to underlie around 160 hectares (400 acres) of land.

Furthermore, it seems that this fire will continue to burn for some time to come; there are no current plans to extinguish it and the eight-mile coal seam constitutes enough fuel to last about 250 years."

via Google Sightseeing where you can find more info.