Exposition Park was the name given to three historic stadiums, located in what is today Pittsburgh, Pennsylvania. The fields were used mainly for professional baseball and American football from c. 1879 to c. 1915. The ballparks were initially located on the north side of the Allegheny River in Allegheny City, Pennsylvania. The city was annexed into Pittsburgh (then often spelled "Pittsburg") in 1907, which became the city's North Side, located across from Pittsburgh's downtown area. Due to flooding from the nearby river, the three stadiums' exact locations varied somewhat. The final version of the ballpark was between the eventual sites of Three Rivers Stadium and PNC Park.
In 1903, the third incarnation of Exposition Park was the first National League ballpark to host a World Series game. The Western University of Pennsylvania (WUP)—known today as the University of Pittsburgh—played home football games at Exposition Park, and also used the park as a home field for the university's baseball team.