Clairton is a city in Allegheny County, Pennsylvania, United States, along the Monongahela River and is part of the Pittsburgh Metropolitan Area. The population was 8,491 at the 2000 census. Under Pennsylvania legal classifications for local governments, Clairton is considered a third-class city. The city was the setting for the movie The Deer Hunter (1978), although the opening scene featuring the "City of Prayer" sign was not actually filmed there (other mill towns in the Monongahela River Valley and elsewhere in the tri-state area were used). That sign was based on the signs in Clairton, but that footage was actually shot in Mingo Junction, OH. It also is home to Clairton Works, the largest coke manufacturing facility in the United States. The Montour Trail, a recreational rail-trail extends from Clairton to Coraopolis, Pennsylvania.