The “Founding Fathers” generally refers to the politicians who were around during the revolutionary war (starting 1775). What you are describing in your [1] seems to be more a reference to the Pilgrims and Puritians (the early North American colonists who showed up around 1620).

The Founding Fathers also did a lot of controlling of some people’s lives (in that they enslaved a lot of people), but they didn’t have to go anywhere to do that.

Anyway, if you want to walk around some history in the US, you can do that in Boston. As you mentioned, a huge factor in the walkability of a city is just having the right population density before cars were invented. The oldest European areas in the mainland US (Spanish areas, in Florida) aren’t super walkable as far as I know.