It’s quite amazing that they managed to put an interstate through the curvy, narrow Virgin River Gorge, but somehow Interstate 15 finds its way through this narrow passage. It’s quite a ride, enjoy it!
This trip is north-to-south. The Virgin River Gorge starts about 75 minutes north of Las Vegas on I-15 and makes for a nice 1/2 day trip. Drive up through the gorge, then have lunch at one of the casinos in Mesquite.