The National Park Service oversees more than 400 parks with two dozen designations, including the Chesapeake & Ohio Canal National Historical Park. (Jim Lo Scalzo/EPA)

The buildup to the National Park Service’s centennial has been bigger than the anticipation of Bei Bei turning 1 or Betty White entering her 10th decade. But the official day has finally arrived. On Aug. 25, a rousing rendition of “Happy Birthday” will sweep through America’s canyons and mountain peaks, seashores and swamps, rivers and battlefields.

To celebrate the milestone, the Travel section assembled a package featuring the 59 national parks. Each protected area received a special tribute, with an overview of its unique character, plus photos that we wish had the same magical capacity as C.S. Lewis’s wardrobe.

Of course, these 59 do not include all of the parks within the NPS system. The department oversees 413 units that fall under 24 designations. For example, there are 83 national monuments, including the Statue of Liberty and Muir Woods, north of San Francisco; 50 national historical parks; 30 national memorials; 19 national preserves; and four national parkways, such as George Washington Memorial Parkway and Blue Ridge Parkway in North Carolina and Virginia.

“To us, all 412 are equal,” said Kathy Kupper, an NPS spokeswoman. “People put the national parks on a pedestal, but legislatively they are the same.” Kupper added that the units all operate under the same “collective mission, leadership and regulations.”

The essential guide to all 59 U.S. national parks

The federal preservation movement has roots in the Antiquities Act of 1906, which gave presidents the authority to protect an extraordinary place as a national monument. President Theodore Roosevelt, for one, created 18 monuments, including the Grand Canyon; his fifth cousin, Franklin D., was responsible for 11. On June 24, President Obama introduced the newest member, the Stonewall National Monument in New York City. Only four POTUSes — Richard M. Nixon, Ronald Reagan, Gerald Ford and George H.W. Bush — did not christen any monuments.

Congress wields more expansive powers over the landscape. Legislators can name or reassign a site under a wider range of categories. That is how William Howard Taft’s Mukuntuweap National Monument in Utah became Zion National Park and how Woodrow Wilson’s Sieur de Monts National Monument in Maine transformed into Acadia National Park. The most recent example: Pinnacles National Monument in central California was crowned the 59th national park in 2013.

“Legislators think that being a national park is more prestigious,” said Kupper. “Perceived or not, some people hold national parks in higher regard.”

To that point, many travelers might assume that the postcard children of the NPS — Great Smoky Mountains, Yellowstone, Grand Canyon — attract the largest number of annual visitors. Nope. Golden Gate National Recreation Area in San Francisco and Blue Ridge Parkway flip-flop for the top two spots, with about 15 million visitors each. The Great Smoky Mountains occupies third place with 10 million guests, but it takes first place among the national parks.

Kupper concedes that trying to wrap your head around hundreds of parks can be challenging, especially considering their diversity. The national parks, however, share some identifiable traits. For example, they are typically large natural areas that possess unique ecosystems and spectacular geologic features.

“They are destination parks,” she said. “You spend more than one day there.”

In addition, Kupper explains that the agency often bans hunting, grazing and other “consumptive” activities in national parks but may permit such activities in national preserves, recreation areas, seashores and lakeshores.

However, for the centennial celebration, all 413 honored guests will receive a slice of cake of equal size and thickness of frosting.

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