6 mistakes you're making when visiting national parks, according to a traveler who's visited 400 of them

• Some US national parks are predicting record-breaking attendance for the summer.
• Insider spoke with Mikah Meyer, who's visited 419 National Park Service sites, for his top tips.
• Meyer said one way to save money is by using gas and lodging locations outside parks.

National parks like Yellowstone and Grand Teton are predicting record visitor numbers this summer, meaning travelers should expect crowds and higher prices.

But there are some ways to avoid long entrance lines and save money on your trips, Mikah Meyer, a national-parks expert, told Insider.

In 2016, Meyer, now 35, embarked on a three-year journey to all the National Park Service sites. By the end of his trip, he had visited 419 destinations, including national parks, preserves, monuments, memorials, and seashores.

In 2019, he became the first person to visit all NPS sites in a single journey, WBUR reported.

Meyer told Insider that in order to see the best of every NPS site while saving money, he spent two years mapping out his route.

When planning a trip to a national park, travelers should avoid six common mistakes to maximize their time and cut costs, he said.

Avoid staying in a park overnight

While many national parks offer lodging within their boundaries, staying in a national park is "the most expensive option," Meyer told Insider.

Meyer recommended finding a short-term rental or hotel in an anchor town just outside park boundaries. He said it would typically be one-third of the price of park lodging.

Not only do you cut costs by staying in an anchor town, but you typically have more dining and lodging options than you would if you stayed in a park, he said.

Don't rely on getting gas inside a park

It takes hours to drive through some national parks, like Death Valley National Park, which is about the same size as Connecticut. In these cases, you'll need a full tank of gas, but fueling up inside a park can be "crazy expensive," Meyer said.

Meyer recommended topping off your tank just before entering a park. If a park straddles two states, sometimes it may be cheaper to cross over into another state, he said.

Meyer recommended the app GasBuddy to figure out where to get the best gas prices.

Don't miss the chance to speak with park rangers

The first thing you should do after entering a park is go to a visitor center and talk to a ranger, Meyer said.

During his three years on the road, Meyer learned that trails are frequently closed for maintenance or safety reasons.

Rangers can save you time by telling you what sites or trails are closed that day so you don't drive an hour to a trailhead only to find it's off-limits. Rangers can also help you tailor your park experience to your interests - like if you want to hike to the best viewpoints, for example.

It's "free expert advice," he said.

Don't assume a park's main entrance is the best one

To avoid long lines, Meyer recommended researching park entrances. GPS systems tend to direct you to a park's main entrance - which might be the most crowded.

For example, most people enter Colorado's Rocky Mountain National Park through Estes Park, but using another entrance in the park's southern section where the roads are less crowded might allow you to get to your destination faster, he said.

Don't rely on cell service for navigation

Meyer didn't have cell service for most of the time he was in national parks.

He recommended downloading Google Maps offline before you enter a park and plugging in your destination so you'll be able to navigate even if you lose service.

If you need internet access in the parks, he recommended purchasing a Verizon unlimited data plan called Visible that costs $25 a month for four lines, comes with a hot spot, and is available on a month-by-month basis with no cancellation fees.

Don't limit yourself to exploring just the 63 national parks

Meyer's biggest takeaway was that some of the most beautiful places in the National Park System are outside the 63 national parks.

Travelers would be remiss to overlook the other 360 sites, like Dinosaur National Monument in Colorado and Utah, he said.

"It's basically the best of everything the National Park Service has to offer all in one site," Meyer said of Dinosaur National Monument, citing its rivers, canyons, accessible hiking, history, and geological sites.

"There's at least one NPS site in every state and territory, so no one is far," he said.

To help travelers, Meyer also offers a trip-planning service on his website and has photos of all the NPS sites on Instagram.