Hot springs national park

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1. Take the Waters: Hot Springs National Park, Arkansas
Sure, warm baths are great and mineral water is nice, but you haven’t lived until you’ve tried a warm bath full of mineral water. At Quapaw Baths and Spa, you can frolic in a thermal pool or shvitz your heart out in the grottolike "steam cave"; both feature therapeutic water pumped from the park's famed springs.
denali national park

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2. Get a Bird's Eye View: Denali National Park and Preserve, Alaska
Not ready to tackle this six-million-acre park on foot? Book a private plane for a “flightseeing” tour and fly like an Aquila chrysaetos (that’s a golden eagle, in case you didn’t know) over Denali’s picturesque glaciers and peaks.
dry tortugas national park

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3. Dive for Treasure: Dry Tortugas National Park, Florida
In 1907, the Avanti, a Norwegian cargo vessel, crashed into a Floridian reef. In 2017, scuba- or snorkel-inclined visitors to Dry Tortugas—seven islands about 70 miles from Key West—can inspect the Avanti’s still-intact bow and stern, along with an otherworldly world of coral reefs.
sand dunes national park

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Think of a sandboard as a slick-bottomed snowboard—and then picture yourself using one to shred North America’s tallest sand dunes (up to 750 feet). Nervous types, fear not: You can also get your kicks on a sled.
hawaii volcanoes national park

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5. Go with the Flow: Hawaii Volcanoes National Park, Hawaii
Kīlauea, one of two active volcanoes in the park, has been spewing lava nonstop since 1983. Picnic on a scenic overlook while watching the earth re-create itself, or hike the volcano’s hardened lava fields to the point where the molten stream collides with the cool Pacific.
Chaco Culture National Historical Park

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6. Look Up and Say "Ahh": Chaco Culture National Historical Park, New Mexico
After you've taken in the park's "great houses"—stone and wood buildings erected roughly 1,000 years ago by the Chacoans, an ancestral Pueblo people—crane your neck to enjoy one of America’s best stargazing sites. More than 99 percent of the park is a “natural darkness zone” with no outdoor lighting—optimal conditions for pondering the universe.