A press release from Interior Secretary Ryan Zinke claims that visitors to U.S. National Parks contributed $34.9 billion to the U.S. Economy. National Park Service spokesman Jeffrey Olson explains.

"Well we have 400 parks in the National Park System from small ones to the big ones, like in your neighborhood, like Glacier and Yellowstone," said Olson. "In 2016 we had more than 330 million visitors to the parks and it is their spending that really drives these local economies and makes a big boost to the nations economy."

As usual, Yellowstone National Park pulled in a lot of visitors, who made a big economic impact on Montana.

"Yellowstone had 4.25 million visitors last year and they spent $524 million in the gateway regions of that park," Olson said. "That supported more than 8,000 jobs and had a $680 million effect mostly to that regions economy."

By comparison, visitors to Glacier National Park spend about $251 million, which helped support around 4,300 jobs and had an overall impact of $339 million in the local economy.