If you want to take a road trip to the seven former Negro League Ballparks listed on the National Register of Historic Places, here is a possible route:
If you want to take a trip to those same ballparks in the order they were listed to see the progression of how they were treated, this is the longer trip for you:
National Register List Date Order Road Trip
If you are looking for a trip to museums that interpret the many different stories associated with the history of baseball, this could be a path for you: