Interstate 70 is the highway that gets you across Utah from Denver. To dip southeast toward Moab, exit the interstate onto U.S. 191, a main artery running all the way south to the Arizona border, skirting Arches' western border, Moab, and the Manti–La Sal National Forest along the way. Alternatively, you can take Route 128, the Colorado River Scenic Byway, traveling just east of Arches. On either road, services can be far apart.
Branching off the main, 18-mile park road are two spurs, one 2½ miles to the Windows section and one 1.6 miles to the Delicate Arch trailhead and viewpoint. There are several four-wheel-drive roads in the park; always check at the visitor center for conditions before attempting to drive them. U.S. 191 tends to back up mid-morning to early afternoon. There's likely to be less traffic at 8 am or sunset.