Here's a suggestion of a source on routes and maps: ACA, the Adventure Cycling Association. Wesbite:
www.adventurecycling.org On the menu bar, the heading "Navigate" lists their resources on routes.
As a North American, I have friends and family in the States, and have travelled a lot Next Door on two wheels, both pedal-powered and motorized.
For the U.S., I have a tilt towards the Pacific northwest, and closer to home (in Ottawa), to the Adirondacks in northern NY state.
But, my preference is to follow the landforms, rather than the political boundaries:
In 2016, I did a rail-and-bike journey to, in, and from the Rocky Mountains, crossing the 49th parallel a couple of times enroute to the Pacific coast. The ACA route map of the western portion of "The Northern Tier" (one the three trans-US routes ACA recommends) was very helpful. Here's the journal of that ride:
www.cycleblaze.com/journals/rockies/ Note that AMTRAK is in my experience a good way to get around, with good discounts for people 65 & older. The VIA Rail network in Canada is much more limited.
One of my most enjoyable routes was a 10-day circuit of the Gaspé Peninsula in SE Québec, the very end of the south shore of the St Lawrence. If you go, the
clockwise route allows you to
descend grades as steep as 17 and 24%. My buddy on that trip lives in Manhattan, and has seen a lot of the world. He said to me as we rode along, "John, this place is amazing -- it's utterly unlike anywhere else I've been."
If time allows a tour of 3-4 weeks: For me, Québec City is one of the magical places of the world. And from there, one could cycle the North shore of the St Lawrence to Tadoussac (mouth of the Saguenay River) and beyond; and then take a ferry to the South Shore to make the circuit of the Gaspé.
Enjoy your planning & dreaming!
John
