So we've agreed on a destination, just need to work out a route. Going to fly into and out of Boston in September for 2-3 weeks. Not quite the Colorado trip I wanted but hey, it's still a US road trip 
So far the only solid 'must do' things are Mount Washington, Toronto and Niagra Falls. I'd like to try and get as far over as Chicago, anyone else done a similar route and what was great/not so great/unmissable/missable etc?

So far the only solid 'must do' things are Mount Washington, Toronto and Niagra Falls. I'd like to try and get as far over as Chicago, anyone else done a similar route and what was great/not so great/unmissable/missable etc?