Summer at a national park means awe-inspiring encounters with the great outdoors. It's the thrill of seeing wildlife and jaw-dropping vistas. However, it also means creeping for hours through crowded park roads and vying for elbow room with thousands of other visitors who all want to enjoy the exact same nature you do.

As the National Park Service celebrates its 100th anniversary this summer, record crowds are expected to pack the system's national park sites. In 2015, a record 307.2 million people visited national parks, monuments, lakeshores and more, according to NPS data. That's a whopping 14.5 million person increase from just the year before.

To put that into perspective, the NPS points out: "Did you know that the national parks draw more visitors than Disney theme parks, NFL games, professional baseball, NBA, and NASCAR… combined?"

So what's the solution to sardine-packed parks? Maybe, park managers say, it might be limiting the number of visitors allowed through the gates.

"We realize that currently we're on an unsustainable course in terms of demands for visitation compared to the ability of the current park system to handle it," Yellowstone social scientist Ryan Atwell recently told the Associated Press.

Yellowstone had an additional 580,000 people visit in 2015, with nearly 4.1 million people crowding the popular park. The experience wasn't a pleasant one for many visitors who were faced with not enough bathrooms or parking spots, as well as garbage cans that spilled over with trash, according to the AP. As people stopped to view wildlife, traffic on some park roadways was back up for as long as two hours.

But not only people were inconvenienced; there was an impact on the park, too.

Rangers issued 52,036 "resource warnings" for behaviors such as "threatening thermal features, approaching wildlife too closely, hiking in restricted areas and 'taking bathroom breaks outside the restroom,' " reported the AP.

In hope of avoiding some issues this summer, the park has added bathrooms and trash cans and has hired additional employees. The park's online visitors' guide encourages guests to be patient, practice "safe selfies," plan ahead, stay on boardwalks, and drive responsibly by using pullouts to look at wildlife or take pictures.

The AP reported that park superintendent Dan Wenk told a group of business people that if the growth continues, he could foresee a limit on Yellowstone visitors during peak season, although probably not for at least a decade.

Tourists crowd around an arch in Utah's Arches National Park. Tourists crowd around an arch in Utah's Arches National Park. (Photo: Vlad Turchenko/Shutterstock)

Overcrowding everywhere

Of course Yellowstone is not the only park with the mixed-bag problem of having an overabundance of visitors.

According to High Country News, on Memorial Day in 2015, highway patrol officers had to close the entrance to Arches National Park in Utah. There was a line of cars waiting to get in that was more than a mile long and, at one trailhead, 300 cars were crammed into 190 spaces.

“This is not the experience people expect, nor the experience we want to provide,” said Kate Cannon, superintendent of the Southeast Utah Group, which includes Arches and Canyonlands.

Park and government officials realize that congestion is an issue, but "most favor finding better ways to manage the crowds rather than seeking to discourage them," the magazine points out. Officials asked the community for suggestions. Ideas included more parking lots, roads and entry booths, as well as "timed entry" or online reservations that would keep everyone from visiting at the same time, and setting a cap on how many people can come into the park each day.

Zion National Park recently had lines of 300 people just to get on a shuttle bus between the park and the visitors center, reports NPR. Shuttles are mandatory during peak times when cars are banned at the park.

"Zion was never designed to see, literally, millions of people," says Jack Burns, who is in charge of crowd management at Zion.

In Grand Teton, NPS has proposed limiting visitors on the Moose-Wilson Corridor to just 200 cars at one time during the busiest summer months. The plan would also lower the speed limit on the popular 7-mile road, which is packed with visitors who want to see grizzly bears, wolves, moose and other wildlife.

people waiting for shuttle bus at Grand Canyon A long line waits for the shuttle bus at Grand Canyon National Park. (Photo: OLOS/Shutterstock)

Reserving your spot

"We're running out of room for people to have these wonderful experiences, and the agency and the partners of the agency are going to have to do a great job of figuring this out and probably figuring it out pretty soon," says Joan Anzelmo, a retired park superintendent in Jackson, Wyoming, told NPR. Anzelmo is now with the Coalition to Protect the National Parks.

We're used to having to make reservations for many other activities, Anzelmo says. We might have to think about our popular national parks in the same way.

"If we want to have these places for another 100 years and beyond, you might not be able to do everything at the same time. There may need to be certain kinds of modest limits on what you can do or how you can access certain areas of a national park."

Is money the answer?

Some experts, however, think limiting park access is not the solution.

Phil Francis, a former superintendent of the Blue Ridge Parkway and member of the executive council of the Coalition to Protect America's Parks, wrote an editorial in the New York Times.

"As park stewards, we must protect our natural resources, to leave them unimpaired for future generations. And of course, nobody likes overcrowded parks. But there are steps that can mitigate the impact of crowds on both the environment and to visitor experience without closing or restricting access to parklands.

Francis gives examples of how offering shuttles and building more boardwalks can often help with crowding issues. Sometimes limiting visitation and car access during peak times may also be an option.

But Francis suggests that the real issue may come down to financial support.

"The biggest impediment to park health is the lack of funding for day-to-day operations and an adequate number of trained employees…Strong federal appropriations would help a lot. Only a fraction of 1 percent of the federal budget goes toward protecting the parks — a grave underestimation, considering the wild popularity of these places."

Mary Jo DiLonardo Mary Jo writes about everything from health to parenting — and anything that helps explain why her dog does what he does.