29.4 miles: 0 hours, 26 minutes
From the Nevada border, I-15 beelines across flat desert with the gray-brown Virgin Mountains to the north and east. As it enters the Virgin River Gorge, vertical gouges in the limestone show where massive amounts of rock had to be removed. The road winds between sheer limestone cliffs, crossing the river several times, before emerging into rugged terrain with a redder hue.
