There’s never really a bad year to put “visit National Parks in the United States” on your to-do list. The big names like the Grand Canyon, Yosemite, and Yellowstone never fail to inspire – but even the smaller parks offer stunning natural beauty and national history. Summer road trips are one of the more popular ways to visit several parks in one vacation, but keep in mind that some cities (including Las Vegas) are good bases from which to explore a few parks without needing to camp or drive long distances. And if you’re the kind of traveler who loves collecting passport stamps, don’t forget to get your U.S. National Parks passport – and then collect those stamps as you visit each park.