"Sprawling out across a whopping and wild 1,754 acres of public land, Rock Creek Park is one of the most awe-inspiring destinations in DC Officially authorized in 1890, it was the third national park to be designated by the federal government. It has something for everyone: a Nature Center for explorers; running, biking, and hiking trails for fitness enthusiasts; equestrian, golf, and tennis centers for sports lovers; and picnic spots, historic forts, a 19th-century gristmill, and concert venues for everyone else. While the verdant grounds are a peaceful escape from urban life, it also offers a planetarium—the only planetarium in the National Park Service, in fact—and the Smithsonian National Zoo. Both are free." - Adele Chapin
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