36 Best Sights in USA

Aerospace, crystals, and the Foucault pendulum are just a few of the things you can learn about here. Housed in a former train station, the museum features live demonstrations and "Giant Screen Movies" in the Dome, a planetarium, and an interactive lifestyle exhibit called Boost!, which tests your strength and memory. You can visit the café or gift shop without paying admission fees.

Run by a dedicated, local nonprofit, this volunteer-staffed 15-acre park near the northern entrance to Joshua Tree National Park educates visitors on the region's celestial and terrestrial attributes. It has an observatory dome with a 14-inch telescope, nature trails that feature desert plants, a meditation garden, numerous sculptures, and an orrery (a 20 billion–to-1 scaled model of the solar system). The campus is always open for walks or stargazing with your own equipment, but the big dome and telescope are only available during the free Night Sky Programs, which are held once a month on the Saturday night nearest the new moon. Programs usually start an hour after sunset and last two hours. The observatory also hosts an annual Night Sky Festival.

William K. Vanderbilt's 24-room Moroccan-style mansion, called Eagle's Nest, sits on 43 acres and houses collections that Vanderbilt acquired as he traveled throughout the world. Summer brings various theatrical performances to the mansion's courtyard. The adjacent planetarium is one of the best equipped in the nation, with a 60-foot domed Sky Theater. Sky and laser shows are held regularly.

This informative and visually stunning observatory on the top of the Four Seasons Hotel offers and indoor and outdoor observation decks overlooking the river. An art-filled gallery of touch screens deliver stories of New Orleans music, food, and Mardi Gras history, as well as original films that touch on Civil Rights history, the Mississippi River, and Hurricane Katrina.

Perhaps most famous for its 40-inch refracting telescope—the largest of its kind in the world—Yerkes was founded in 1897 by George Ellery Hale and financed by Charles T. Yerkes. On a tour of the observatory, visitors get a chance to enjoy the nightscape and then gaze up at the celestial bodies through one of the other two modern telescopes on the campus. The surrounding 77 acres of parkland, which narrowly escaped residential development in 2007, were designed by John Olmsted, brother of Central Park landscape designer Frederick Law Olmsted. Wear sensible shoes: The climb to the telescope is up a 39-step spiral staircase.

With the most spectacular views of the crater and lava dome of Mt. St. Helens, this observatory also has exhibits that interpret the geology of the mountain and explain how scientists monitor an active volcano.