Aspen Colorado to International Falls, Minn

[markusoon]

My wife and I are going to be driving from Aspen Colorado to International Falls Minnesota the last week of August. We would appreciate suggestions on route to avoid cities and congestion, see nice scenery, national and state parks, nice campgrounds possibly off-the-beaten track locations, lakes/rivers, etc. We plan on taking about four days to get there. Incidental to this road trip we would also like to do a three day weekend trip with my son and his wife out of International Falls. Would love suggestions on lodges, packages in Canada or Minnesota (maybe on a lake, reasonably remote, good fishing...might consider a fly-in depending on cost). Thanks in advance for any advice.