Arizona is home to some of the most amazing, scenic, and popular national parks in the United States. The Grand Canyon, the Painted Desert and Petrified Forest, Wupatki and Sunset Crater, and Walnut Canyon, among others, are all within two hours of Flagstaff. Typically, it would cost a family of four $20 to $25 to enter each park, but for a couple of special weekends, these amazing places will be open and free to all. Tie in some low-cost camping at or near one of the parks, and — presto! — there's a weekend getaway in which you'll take in some of the state's greatest places for just the cost of gas and food. Of course, the Canyon is worthy of a week unto itself, but a full day on the south rim, tied in with a circuit of Wupatki/Sunset Crater, makes for an inspiring day capped by a night camping next to the lava flow at Sunset Crater. On day two, head east of Flagstaff to Walnut Canyon and the colorful duo of the Petrified Forest and the Painted Desert. If there's time either on the drive up north or the return to the Valley, be sure to stop at Montezuma's Castle in Camp Verde. On any weekend, it's worth the trip.