The Glace Bay Miners of the old Cape Breton Colliery League played their home games at South Street Field. At 59°57’02.75″ west, this the most easterly park in Organized Baseball history. The field is still in use today, assuming that the softball field on South Street is the former baseball field.
The Miners were members of the Colliery League for its entire three-year (1937-39) existence as a pro loop. They were also members of the league prior to 1937 when it operated as an amateur league. The transition to professional baseball began in 1935 as teams were allowed three imports. The league became fully professional in 1937. The town of Glace Bay renovated the facility in preparation of professional baseball in 1937 by fixing up the bleachers and fences. Further upgrades were made in 1939. These consisted of moving the fences in eight feet and standardizing the height at eight feet. The Miners had to pay rent to use the facility while local amateur teams got to use it for free.
Major Leaguers who called the South Street Field home were Freddie Maguire of the 1937 Miners (618 career MLB games with the Boston Braves). The 1938 Miners featured Major League veterans Del Bissonette (604 career games with the Brooklyn Dodgers) and Bill Chamberlain (12 games with the White Sox in 1932). Bissonette also served as the Miners manager. The 1939 teams was managed by former Philadelphia Athletic and Detroit Tiger Roy Moore.
Assuming that I am correct, the field was later transformed into softball field. Due to the smaller dimensions used for softball, home plate was moved up 100 or so feet. I am not sure when this conversation took place.
As on early 2017, the site is scheduled for an upgrade.