Touring the Monticello.
The grounds are beautiful. And more expansive than I would have thought.
I learned so much about Thomas Jefferson, both good and bad. I also learned alot about life at that time, and the Charlottesville area. I was most interested in the fact that he was a brewer.
And the books. The man read.... A LOT. Pretty much the internet of the day, and he was on broadband! He also donated much of his collection to start he Library of Congress.
Too much to put into words here, but if you get a chance, go. More than once if you can, you miss some stuff the first time.