Scenic, Historic and Backcountry Byways in Colorado
I've driven 20 of the designated Scenic Byways in Colorado. Most of those routes are in the mountains but a few are on the eastern plains and Lariat Loop is essentially within the bounds of the Denver Metroplex.
There are several other roads around the state I would include in the lists below but they haven't been officially designated.
Scenic, Historic and Backcountry Byways in Colorado
In Leadville, along Top of the Rockies National Scenic Byway
Photos courtesy of TheArmchairExplorer, CCA-by-SA 4.0 License
Map courtesy of Cartesia MapArt Terrain