The mean geographic center (calculated by averaging the latitudes and longitudes of ballpark locations) of the American League is near Monroe City, Missouri. The mean geographic center of the National League is on Logan Ridge Road, near Highlandville, Missouri.
Nearest towns to the mean geographic centers, by division:
AL West: Caliente, NV.
AL Central: Addison, IL.
AL East: Upper Marlboro, MD.
NL West: Boulder City, NV.
NL Central: Birds, IL.
NL East: Bailey, NC.
Mean geographic centers for popular rivalries:
Red Sox/Yankees: at the end of North Maple Street, East Hampton, CT.
Dodgers/Giants: in the hills south of Coalinga, CA.
Cards/Cubs: two miles east of Heyworth, IL.
Same metro area:
Cubs/White Sox: N Union Ave at W Kinzie St, Chicago.
Dodgers/Angels: Emmons Way, Santa Fe Springs.
Giants/A’s: In San Francisco Bay, near Encinal High School, Alameda.
Mets/Yankees: On Rikers Island.
Yes, really, it’s true…if you meet the Mets and Yankees halfway, you end up in prison.