Old-Biscuit wrote:
I-80 to Cheyenne WY then I-25 to Denver
Definitely nothing 2 lane...............boring but no 2 lane
What he said! Added bonus, you'll likely have a tail wind most of the way across Wyoming. As an alternative to going all the way to Cheyenne, you could take US 287 from Laramie to Fort Collins. While technically a 2 lane road, there's some 4 lane out of Laramie, and many climbing/passing lanes between the state line and Fort Collins. Good, easy drive that way and saves you some time and distance.