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, 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 Allegheny 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.

Local newspapers referred to the general area along the Allegheny waterfront as "the Exposition grounds", named for other "expositions" that would be shown there, including horse racing and circuses.

Exposition Park I was the first venue in Pittsburgh that hosted major league baseball. In 1882, the club now known as the Pittsburgh Pirates—then known simply as Allegheny, or informally as "the Alleghenys"—began play at Exposition Park as a member of the American Association; however, after one season a fire and flooding of the field from the nearby river forced a second park to be built.

Despite its reason for construction, Exposition Park II was built closer to the river. The Alleghenys played at the second incarnation of the park for the first part of the 1883 season, but after the game of June 9, the club decided to return to Exposition Park I, starting with the game of June 12. The Allegheny club abandoned Expo II in 1884, moving to Recreation Park, which was several blocks north and out of the flood plain. The final usage of Expo II for baseball came in the last week of August, 1884, where the struggling Union Association club dubbed the Pittsburgh Stogies finished out their schedule after moving from Chicago.

During 1884 through 1889, the ballpark was primarily a racetrack used for many types of events: horse racing, bicycle racing, foot racing, and various exhibitions such as circuses. The grandstand ran roughly west-to-east, bordering South Avenue. The roof included five pyramid-shaped turrets. In 1887 came a short-lived attempt to rename the facility Gentlemen's Driving Park, ads for which typically appended "formerly Exposition Park". When the Players' League club began, they reconfigured the former racetrack for baseball purposes, including retaining a couple of the turrets left over from the track's grandstand.

While the Alleghenys were playing home games at Recreation Park, owners John Beemer and M. B. Lennon of the Pittsburgh Burghers reconfigured the former racetrack into a proper baseball park near the former sites of Exposition Parks I and II, approximately two blocks west of where PNC Park sits today. Exposition Park III included a roofed wooden grandstand around the infield, in the northeast corner of the block, and open bleacher sections extending to the right and left field corners. Total capacity was about 10,000 spectators. The seats faced the Allegheny River and the Point. The Burghers played at the stadium during the 1890 Players' League season—both the team and league's only season in existence. On June 10, 1890, Jocko Fields of the Pittsburgh Burghers hit the first home run at Exposition Park III.

The recurrent flooding which plagued the location through its entire existence led to this editorial comment about the Brotherhood (Players' League) club: "They have the most level grounds in the country. Exposition Park is covered with water."