Antietam is an exceptional place for a multitude of reasons. I assume that during the summer the crowds can get rather large. If you hit it just right then you can visit it when there arent many people around. It has a really weird vibe to it. It is somber…yet beautiful. Its a very hard place to describe.
Regarding it being a great place to ride, it certainly is. Bikes are welcome most everywhere.
I think all Americans should try and visit here as well as Gettysburg. Me? I prefer Antietam hands down.