The road to the summit of Clingmans Dome in Great Smoky Mountains National Park is a showstopper. It curves through corridors of spruce and fir, emerging from the trees to kiss scenic overlooks, where you can kill the engine and gaze out at the humpback expanse of the Smokies. The tallest mountain in Tennessee, Clingmans Dome, is one of the greatest attractions for hikers who visit the park. But getting to its top can be an adventure in its own right; drivers are more than 6,000 feet above sea level, navigating roads with nerve-racking  drop-offs. One wrong turn, and you could tumble down.

On July 15, 2019, that’s what happened when a Chevy Cobalt plunged more than 50 feet from a stretch of Clingmans Dome Road near its terminus, killing the driver and injuring a passenger. The incident might sound like a freak tragedy. But in Great Smoky, the dramatic crash was the latest in a history of deadly motor vehicle accidents along the park’s side-winding roads.

Statistically speaking, you are most likely to die in a vehicle accident in Great Smoky, which is saying something for a park whose 522,427 acres of mountains and rivers offer ample opportunities for falling or drowning. “On record, we’ve seen roughly 500 fatalities since the inception of the park” in 1934, says Dana Soehn, park spokesperson for Great Smoky. “About 170 of those deaths are related to motor vehicle accidents.”

Every national park has its own hazards that are most likely to cause serious injuries and deaths; and some of them might surprise you. The outdoor travel site Outforia recently ranked the parks by number of deaths after it obtained systemwide data spanning 2010 to the start of 2020 via a Freedom of Information Act request and categorized the fatalities. A heart attack would be classified as medical/natural death, while tripping and cracking your skull on a rock — or losing your balance on a ledge — counts as a fall.

Of the 62 national parks in the system at the time (a 63rd has just been added), these 10 have the highest number of fatalities.

1. Grand Canyon, Arizona (134 deaths)

2. Yosemite, California (126 deaths)

3. Great Smoky Mountains, Tennessee and North Carolina (92 deaths)

4. Sequoia & Kings Canyon, California (75 deaths)

5. Yellowstone, Wyoming, Montana and Idaho (52 deaths)

6. Denali, Alaska (51 deaths)

7. Mount Rainier, Washington (51 deaths)

8. Rocky Mountain, Colorado (49 deaths)

9. Grand Teton, Wyoming (48 deaths)

10. Zion, Utah (43 deaths)

A handful of national parks recorded no deaths between 2010 and 2020: Gateway Arch, Missouri; Petrified Forest, Arizona; Kenai Fjords, Alaska; American Samoa, American Samoa; North Cascades, Washington; Isle Royale, Michigan; Kobuk Valley, Alaska; and Gates of the Arctic, Alaska. These parks also tend to have the fewest visitors.

The Outforia ranking does not include all 2020 deaths, some of which occurred during the nationwide surge of mid-pandemic visitation that parks experienced this past year. But as the pandemic heads into its second year, the ranking offers some helpful insights for visitors about where and how accidental deaths can happen. Because at least at the most dangerous national parks, the greatest dangers might not be what you think they are.

Take the Grand Canyon, one of the most iconic symbols of the American landscape and the deadliest national park on the Outforia ranking. Given how many visitors pose near the rim of the canyon for selfies, you might assume that most visitors have died by falling from its high ledges.

But while some visitors have indeed suffered this grisly fate, the most common fatalities in the park result from natural medical emergencies. Many of these emergencies begin with heat exhaustion from the infernoesque temperatures at the bottom of the canyon, which can reach as high as 120 degrees Fahrenheit during the summer. This, combined with more than 4,000 feet of elevation gain for hikers ascending the canyon from the bottom, can be dangerous for anyone with cardiac or respiratory conditions, diabetes, or little experience in a desert climate.

“If you’re simply in that environment and not exerting yourself, you still might experience heat exhaustion,” says Joelle Baird, public affairs specialist for Grand Canyon National Park. Baird is familiar with the dangers of the canyon, having served as a ranger with the park’s preventive search-and-rescue team (P-SAR), which tries to educate hikers before they get in trouble.

Baird says P-SAR teams go beyond asking visitors whether they have sufficient water, snacks and appropriate clothing, though those are all important. They also ask hikers why they have chosen a certain trail. If they know the motivation, they can suggest a more manageable hike. “Sometimes it’s just, ‘I want to see the river,’ ” she says. “And that’s easy to work with. You don’t have to go down to the bottom of the canyon to see the river.”

In addition to overambition, one particularly troubling red flag that P-SAR teams encounter is hiker groupthink. “Sometimes hiking in a group can be dangerous because no one wants to be the squeaky wheel,” Baird says. “They may be having trouble” but be reluctant to speak up.

Falls might be less endemic to the Grand Canyon than one would expect, but they are the top cause of death in Yosemite, the second-most-dangerous park. And it’s not just because of climbers tackling the famed peaks of Half Dome or El Capitan. Instead, more falls occur as a result of taking selfies near treacherous terrain, or failing to pay attention and ignoring risks. “While Yosemite is certainly a destination for rock climbing and higher-risk activities, the majority of our search and rescues that we see, anecdotally, are people who are engaging in traditional park activities such as casual hikes on marked trails,” park ranger Jamie Richards says.

Posing for photos or selfies, in particular, has emerged as a cause of fatal falls. In the past decade, Yosemite visitors have plunged to their deaths from Nevada Fall, Taft Point and Vernal Falls while attempting to take selfies or pose for others. The Vernal Falls incident, which occurred in 2011, was especially grim. Three park visitors fell from the top of the 317- foot-tall cascade. One had been posing for a photo near the brink of the cascade when she lost her footing and fell into the water. Two bystanders tried to extract her, only to be swept over the waterfall as well.

Even in more tranquil park territory, spur-of-the-moment decisions can lead to falls. According to Richards, the ragged beauty of Yosemite’s jagged peaks, misty waterfalls and towering Ponderosa pines can distract visitors from subtle hazards like a lingering patch of ice or an unsafe off-trail detour, such as scrambling over slippery rocks to get to the base of a waterfall. “It just takes one false step to lose your balance, fall, break an ankle or hit your head,” Richards says.

And if the water coursing over the rocks is strong and abundant enough, you could drown. Beyond falls and natural death, drownings are the most common cause of death in Yosemite. The park website warns visitors to be cautious when hiking the Mist Trail, which ambles past Emerald Pool. This shallow river-fed lake can look inviting on broiling summer days, but beneath its glassy surface are extremely strong currents. Despite the warning signs posted around the lake, some visitors have waded into the seemingly placid waters of Emerald Pool, only to get whisked away by the current.

 Drowning is also a noteworthy danger in Great Smoky Mountains National Park. “We have boulder-strewn swift river systems throughout the park, and we don’t recommend swimming in them,” Soehn says. “The water can rise unpredictably if there’s rain in the upper mountains. It may be kind of sunshiny at the lower elevations, and people can be taken off guard” by the current. Sixty drownings have been recorded in Great Smoky since the park’s opening.

As for the auto accidents that reign as the Great Smoky’s top fatality, Soehn says this hazard was built into the park, which was conceptualized and designed when auto touring was becoming popular. “One of the largest advocacy groups for the creation of the park was an auto touring group,” Soehn says. “They had been driving out west, doing scenic touring, and they realized what an opportunity it could be, to bring tourism into their home in the eastern U.S.”

The 384 miles of roadway in the park were carefully designed to fold into the craggy landscape and align with the topography of the mountains. “That is what presents the challenge for drivers,” Soehn says. While visitors may understand that they’ll be doing a lot of driving, “they need to approach it differently than they would for their daily commute on a highway.”

You can learn about the dangers posed by any park simply by visiting its website before your trip, and paying attention to warnings in visitor centers or from P-SAR teams while you’re there. Being prepared, watching your surroundings and knowing your recreational limitations can be the difference between life and death. Remember: You want to come home with exciting stories. You don’t want to become a cautionary National Parks tale yourself.

Howard is a writer based in Boston. His website is mileshoward.com. Find him on Twitter: @MilesPerHoward.

Please Note

Potential travelers should take local and national public health directives regarding the pandemic into consideration before planning any trips. Travel health notice information can be found on the Centers for Disease Control and Prevention's interactive map showing travel recommendations by destination and the CDC's travel health notice web page.