I took a history of baseball class in college. I know I mentioned it here yearrrrrrrrs ago. It was awesome, and counted as a normal history course. You can actually track things like wars, politics, and the economy through baseball. The professor was like 1000 years old, and his wife came with him to every class. (So cute!) He was a consultant for the movie Field of Dreams and one other. He had written books and interviewed Babe Ruth among other famous ball players.
Anyway, he talked about ballpark dimensions, how they evolved, and why they were unique at the old parks.
I loved that class. I thought it was going to be a blow-off class, but I actually learned a lot.