Monessen is a city in southwestern Westmoreland County, Pennsylvania, United States, located along the Monongahela River.With restructuring of the steel industry in the later 20th century and loss of jobs, it is considered a Rust Belt borough in the "Mon Valley" of southwestern Pennsylvania.Named for the Monongahela River and the industrial German city of Essen, Monessen was created by land speculators fairly late in the history of the Mon Valley, after neighboring towns had already been settled.James M. Schoonmaker, who made his fortune in coke, owned a controlling interest in the land company.[4] In May 1897, National Tin Plate Company, founded by William Donner, began building its mill, thus becoming Monessen's first employer.[5] Beginning in the middle to late 1960s, the region's manufacturers, especially the steel industry, found it harder to compete, which led to employee layoffs.In January 2010 the first female mayor, Mary Jo Smith, was sworn in at the Monessen Municipal Building.The climate in this area is characterized by hot, humid summers and generally mild to cool winters.Across the Monongahela River in Washington County, Monessen runs adjacent to Carroll and Fallowfield Townships and North Charleroi (with a direct connector via Charleroi-Monessen Bridge).
Map of the Pittsburgh Tri-State with green counties in the metropolitan area and yellow counties in the combined area