Even though distances seem vast in the western United States, it's possible to visit more than one of the region's national parks in a single trip. In fact, people often combine visits to Yellowstone with Grand Teton, Yosemite with Sequoia, and Zion with Bryce Canyon.
You can knit the parks of the California desert (Death Valley, Joshua Tree, and Mojave Preserve) into an itinerary that might even leave you time to stop off in Palm Springs. A popular trip for families is a drive through Badlands National Park and the Black Hills of South Dakota, on through Devils Tower, to Yellowstone. It's not a small stretch, but it's doable if you have more than a week.
Although it can be a lot of fun to combine several national parks in your vacation trip, try not to make the all too common mistake of attempting to see everything there is to see in too short a period of time. Be realistic about how much you want to see at each park, and create an itinerary that lets you thoroughly enjoy one or two aspects of a park rather than just glimpsing every corner as you speed by. And try to schedule a little relaxation time, especially for trips of more than a week -- perhaps loafing in the campground one afternoon, or lounging by the motel swimming pool.
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