Buy a parks pass. With entry fees of $20 per vehicle at the major national parks, consider a National Parks Pass ($50; covers entrance fees at national parks, monuments, and recreation areas for one full year from first use). Contact the National Park Service (www.nps.gov, or (888) 467-2757) or purchase a National Parks Pass at any national park.
Do your driving midday. Plan to get to your destinations in time to enjoy the dramatic light of morning or late afternoon.
Pay attention to conditions. Weather is highly variable, especially depending on elevation, which ranges to more than 11,000 feet. Spring and fall have the mildest temperatures and are the best times to visit (although early or late snows can force closures of some roads).
Plan ahead. Destinations can be widely spaced. Make sure that you keep your gas tank full and carry extra water and food in case you have problems.
Call for road conditions: Arizona, (888) 411-7623; Nevada, (877) 687-6237; Utah, (800) 492-2400.