National Park Service National parks: Where we go and where we don’t Much of the Park Service’s land in the West is poorly visited and little-known.

Though the West’s national parks endure, visitation to specific sites constantly varies, subject to the whims of gas prices, social media and even books and movies.

“Sites really tend to fluctuate with special events and what’s going on in popular culture. That gives them a pretty good push for a year or two,” says Pamela Ziesler, National Park Service statistics coordinator. When a documentary about John Muir came out in 2012, visitors flocked to the Muir Woods near Mill Valley, California. And after Cheryl Strayed’s book Wild (and the 2014 movie based on it) became popular, so did the Pacific Crest Trail: In 2015, 3,000 people applied for a permit to complete the entire 2,650-mile path, compared to 300 people in 2012.

Gary Cziko, cc via flickr

Ziesler says cheap gas and a growing population also draw tourists. Rocky Mountain National Park, on Colorado’s Front Range, saw more than 4 million visits in 2015, nearly twice as many as a decade earlier, mainly because of the park’s proximity to rapidly expanding Denver. (See graph.)

Still, many of the park system’s more than 400 units exist under the radar of most travelers, meaning that there is still plenty of open space in parks, preserves, monuments, historic sites, national seashores and battlefields. One such lesser-known treasure is Wrangell-St. Elias National Park and Preserve in Southeast Alaska. While Wrangell-St. Elias is the largest unit in the system —13.2 million acres — it’s so remote that fewer than 100,000 people find their way to it each year.

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