In 1962 a trash fire accidentally ignited an exposed coal vein in the town of Centralia, Pennsylvania. Over forty years later, the mines underneath the town are still on fire -- and will continue to be for at least another 100 years. The population has been reduced from over a thousand down to just eleven! Smoke and steam continue to pour out of the ground.
Sounds like a pretty creepy place? Silent Hill screenwriter (and gaming geek) Roger Avary agrees! He apparently researched Centralia while writing the screenplay; Silent Hill, in the film adaptation, is a West Virginia coal town with the trademark fog/smoke.