Why missing one $2 expense could derail your whole national park trip

National park tourism is booming. But an idyllic adventure into the great outdoors can be derailed by overlooking an important aspect of trip planning: advance permits and reservations.

Some of the most frequently visited parks require people to book ahead for access to popular attractions such as heavily trafficked hikes, roads and campgrounds. Some require advance tickets for full park entry.

This means travelers can't necessarily bank on showing up spontaneously to a national park and getting the experience they desire. Fail to secure this paperwork, which is typically free but can carry a processing fee of as little as $2, and you might not even get in. Since reservations can be in high demand, it's necessary to plan ahead.

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Advance permits are "one of the biggest things people miss," said Mary Cropper, a travel advisor and senior U.S. specialist at Audley Travel.

The rules vary from park to park. Sometimes, there may be ways to skirt them for travelers unable to get one in advance.

Reservations are among the ways parks are addressing congestion.

Americans flocked to national parks in 2021 and 2022 as a way to get outside and vacation domestically during the Covid-19 pandemic era, at a time when traveling overseas was difficult due to health concerns and international travel restrictions.

Eighteen parks broke annual visitation records in 2021, according to National Park Service data. One of them, Hot Springs National Park in Arkansas, saw record visitors last year.

Overall visits to national parks jumped 5% in 2022 versus the year prior, to 312 million recreation visits. While not a record, visitation last year was only about 5% lower than its peak in 2016, the year of the National Park Service, or NPS, centennial, said NPS spokesperson Kathy Kupper.

The NPS doesn't forecast future visitation, Kupper said.

Most parks currently do not require reservations for entry, though the number is expected to increase in future years.

Many parks that do require reservations began implementing them during the pandemic era, though some started before 2020.

Glacier National Park, located in Montana, did so in 2021, for example. Yosemite National Park, in California, did so in 2020, though the park eliminated the requirement for 2023.

These reservations are assessed per vehicle. Parks require them for motorists to access certain roads, such as the Going-to-the-Sun Road in Glacier National Park.

The following parks have a vehicle reservation in effect for 2023:

• Acadia National Park, Maine

• Arches National Park, Utah

• Glacier National Park, Montana

• Haleakalā National Park, Hawaii

• Rocky Mountain National Park, Colorado

Zion, Rocky Mountain, Acadia, Yosemite and Glacier were among the top 10 most-popular national parks in 2023, according to NPS data.

Separately, Zion National Park in Utah requires an advance permit — available by lottery — for visitors to access its Angels Landing hike, among the most-popular destinations in the park. Yosemite requires a permit to hike to the top of Half Dome, as does Arches for its Fiery Furnace hike.

Muir Woods National Monument in California also imposes an advance reservation for parking.

While Yosemite did away with its reservations to access the full park this summer, the park kept them for three weekends in February to help manage crowding during the Horsetail Fall event, during which the waterfall flowing off the El Capitan rock formation glows orange in ideal sunset conditions.

Language on Yosemite's website suggests broader park reservations may return in future years.

"Yosemite has been grappling with congestion — even gridlock — for decades," according to its website. "We want to build from the lessons learned from the last three summers of managed access."

Additionally, many parks require separate reservations to access certain campgrounds, or wilderness permits for overnight backpackers.

"If you plan to spend the night in or around the park, you should have reservations for lodging, camping, or backpacking," according to the Olympic National Park website. "In the summer months, especially on the weekends, campgrounds and motels can fill quickly."

Visitors can make reservations online at Recreation.gov or via the Recreation.gov call center at 877-444-6777. Reservations carry a nonrefundable processing fee, ranging between $2 and $6.

In addition to the processing fee, visitors must pay a park's standard entrance-pass fee or present a National Park Service annual multipark pass.

Reservations and permits generally become available online months in advance. For those unable to score a reservation, parks generally release additional tickets closer to the visit date, sometimes just a day ahead. In both cases, they tend to sell out quickly.

There are many details that vary between parks. For example, some vehicle reservations are valid for multiple days of park access and others for just one day. Some parks require visitors to book for a certain entry time, requiring motorists to arrive within a specified time frame.

However, there are some ways around reservations for those unable to secure one.

For example, vehicle reservations are generally only in effect for peak times of day and for certain times of the year. That means motorists can access the park without a reservation outside those peak hours and months.

For example, Glacier's Two Medicine vehicle reservation is in effect from July 1, 2023, to Sept. 10, 2023, 6 a.m. to 3 p.m. local time. Tourists visiting outside those dates and times generally don't need a reservation, according to the Glacier website.

Similarly, visitors can often bypass permit requirements if they've booked amenities including lodging, camping, transportation or commercial activities such as tours located in restricted park areas.

"A lot of times, individual permits are way harder to get than a hiking guide who has those [permits] for the whole summer season," said Mike Augustine, a travel advisor and U.S. national parks specialist at Mountain Travel Sobek.

If you're planning to visit a national park, check the park's website for up-to-date information on reservations, road closures and other important information, Cropper said.

"Planning ahead for national parks is what will set you up for a really smooth trip," Cropper added.