When George Gibson arrived in Pittsburgh in 1905, the Pirates played at Exposition Park. Located along the banks of the Allegheny River (between present day PNC Park and Heinz Field), the ballpark was prone to flooding. So much so, in fact, that the Pirates routinely scheduled long road trips to avoid the Allegheny at certain times of the year ^[1]. In 1903, when the Pirates and Red Sox were locked in a battle to claim the first ever World Series, game 4 had to be postponed for a day because of such extensive flooding at Exposition Park^[1].

It was also in 1903 that the Pittsburgh Pirates owner Barney Dreyfuss began looking for land to build a replacement to Exposition Park. He eventually secured a 7-acre plot of land across from the Carnegie Library of Pittsburgh. It is said that he spent less on the land so that he could spend more on the ball park[3].

On March 1, 1909 ground was broken on the new ballpark, a $1 million dollar steel and concrete structure that was build in 122 days [3].

The last Pittsburgh Pirates game played at Exposition Park against the Cubs on June 29, 1909. 5,545 fans were on hand to witness the Pirates win by a score of 8-1. In 1914 the stadium would be used for the Federal League’s Pittsburgh Rebels, leaving George Gibson with the distinction of having recorded the last National League hit in the park [4].

Forbes Field opened the next day, June 30th, and once again saw the Pirates face off against the Chicago Cubs [5]. This time, nearly 6 times as many fans showed up! Some 30,338 were on hand to open the new park. Johnny Evers was the first ever batter at the new ballpark. He was hit by a pitch and would later score [4]. The first Pirates player to record a hit at Forbes was George Gibson [3].

The Cubs would go on to beat the Pirate 3-2.

Forbes Field was closed on June 28, 1970 and demolished in 1971 [3].
Some sections of the original stadium do remain in Pittsburgh, however, and are easily accessible to the public.

Sources:

[1], [2] – http://pabook2.libraries.psu.edu/palitmap/ExpositionPark.html
[3] – https://en.wikipedia.org/wiki/Forbes_Field#cite_note-Dia89-8
[4] – The Pittsburgh Pirates Encyclopedia 2nd Edition, by David Finoli & Bill Ranier (page 519-520)
[5] – www.retrosheet.org