We have driven US-191 a few times. It is mostly two lane. There are relatively steep climbs and descents around Flaming Gorge, a 9,000' pass between Price and Vernal and a steep Climb out of Vernal. Consult the Mountain Directory for details.
There is a lot to see and do along this route.
Monument Valley, Bluff, Blanding Area:
Monument ValleyUT-261 the Moki Dugway Goosenecks State ParkHovenweep National MonumentNatural Bridges National MonumentBluff FortSouth Fork of Mule Canyon and House on FireThe Valley of The GodsSand Island Petroglyphs Edge of the Cedars State ParkDinosaur MuseumMoab/Monticello area:
Kane Creek RoadPotash Lower Colorado BywayUpper Colorado River UT-128 Scenic BywaySago CanyonDead Horse Point State ParkArches National ParkCanyonlands National ParkNeedles DistrictNewspaper RockVernal Area:
Utah Field House State ParkDinosaur National MonumentUS-191 from I-80 (Rock Springs) is in my opinion a good route and takes you through the Tetons and in the South Entrance to Yellowstone if it will be open when you need to get there. There is a Walmart in Rock Springs where you can stock up if you need supplies.
