America’s national parks draw hundreds of millions of visitors every year, and the overwhelming majority go home with nothing worse than a sore pair of legs and a phone full of photos. But a handful of trails have earned national reputations for danger — not because they’re cursed, but because they combine extreme exposure, heat, altitude, water hazards, or sheer popularity in ways that punish small mistakes. Below is a roundup of the hikes that show up again and again in National Park Service mortality data and search-and-rescue reports, along with what makes each one risky and the official park trail page so you can plan ahead.

1) Angels Landing — Zion National Park, Utah
Angels Landing is probably the single most famous “dangerous hike” in the entire park system, and for good reason: the final half-mile climbs a narrow sandstone fin with thousand-foot drop-offs on both sides, with only a series of bolted chains to hold onto. The trail’s danger comes less from technical difficulty and more from volume — for years it was one of the most heavily trafficked exposed routes in the country, which meant hikers passing each other on ledges barely wide enough for one person. The Park Service has since instituted a permit lottery system to cap daily hikers, which has dramatically reduced the crowding that once made the chains section so hazardous.

Before attempting it, check current conditions and the permit requirements directly through the park.
Trail info: https://www.nps.gov/zion/planyourvisit/angels-landing.htm

2) Half Dome — Yosemite National Park, California
Half Dome’s final 400 feet are a near-vertical granite slab fitted with steel cables and wooden cross-planks that hikers use to pull themselves to the summit. It is one of the most sought-after day hikes in the country, and also one of the deadliest, with falls from the cables and the approach trail accounting for over a dozen deaths in the past two decades. Conditions change the calculus fast: the granite becomes dangerously slick when wet, afternoon thunderstorms roll in with little warning at elevation, and the sheer number of permit holders on the cables at once creates bottlenecks in an extremely exposed spot.

A permit is required for the cables, and rangers strongly discourage attempting the route in wet weather or during storms.
Trail info: https://www.nps.gov/yose/planyourvisit/hdpermits.htm

3) Mist Trail (to Vernal and Nevada Falls) — Yosemite National Park, California
The Mist Trail is short, scenic, and extremely popular — which is exactly the problem. The trail’s granite steps run right alongside the Merced River and the base of two waterfalls, and the spray from the falls keeps the rock perpetually damp and slippery. Despite guardrails and prominent warning signs, hikers have repeatedly climbed over barriers to get closer to the water or a better photo, and the combination of fast current, slick rock, and steep drop-offs has made this one of the deadliest short hikes in any national park.

Stay on the marked trail and behind all railings, especially near the top of the falls where the current is strongest.
Trail info: https://www.nps.gov/yose/planyourvisit/mist_trail.htm

4) Bright Angel & South Kaibab Trails — Grand Canyon National Park, Arizona
Unlike most entries on this list, the Grand Canyon’s corridor trails aren’t dangerous because of cliffs or technical terrain — they’re dangerous because of heat. Temperatures at the canyon floor regularly exceed 110°F in summer, and the trek back out involves thousands of feet of elevation gain in direct sun with no shade. Most Grand Canyon fatalities are tied to medical emergencies, heat exhaustion, and dehydration rather than falls, and the park logs hundreds of heat-related rescues every year, the majority of them on Bright Angel Trail.

Hike during cooler months when possible, start before sunrise in summer, and carry far more water than you think you’ll need.
Trail info: https://www.nps.gov/grca/planyourvisit/corridor-trails.htm

5) The Maze District — Canyonlands National Park, Utah
The Maze is one of the most remote and disorienting trail networks in the entire park system — a labyrinth of canyons, fins, and slot passages so confusing that even experienced backcountry hikers have become lost for days. There’s little to no cell service, water sources are scarce and unreliable, and a wrong turn can mean miles of backtracking in extreme heat. The danger here isn’t a single cliff or cable section; it’s the cumulative risk of isolation, navigation error, and dehydration in a landscape that offers almost no margin for error.

A backcountry permit, detailed route planning, and a satellite communicator are strongly recommended before entering.
Trail info: https://www.nps.gov/cany/planyourvisit/maze.htm

6) Longs Peak (Keyhole Route) — Rocky Mountain National Park, Colorado
Longs Peak is the tallest mountain in Rocky Mountain National Park, and its standard route is technically a hike for most of the way — until it isn’t. Beyond the Keyhole formation, hikers face exposed ledges, a steep “Trough” gully, and a final scramble across sloped granite slabs with significant exposure on either side. Add Colorado’s notorious afternoon lightning storms, which build quickly above treeline, and the altitude itself (the summit sits above 14,000 feet), and you have a route that has claimed climbers who started the day with clear skies and good intentions.

Start before dawn so you’re off the exposed sections before afternoon storms typically arrive, and turn back at the first sign of thunder.
Trail info: https://www.nps.gov/romo/planyourvisit/longspeak.htm

7) Devils Garden Trail (to Double O Arch) — Arches National Park, Utah
Arches’ primrose path turns into a genuinely demanding route once you continue past Landscape Arch toward Double O Arch. The trail narrows to thin sandstone fins with significant drop-offs on both sides, and there’s essentially no shade for the entire route. Combined with Moab’s brutal summer heat, hikers who underestimate the distance and exposure have suffered fatal heat illness, and the narrow fin sections have also been the site of fatal falls.

Carry at least one gallon of water per person in summer and avoid the exposed fin sections if you’re uncomfortable with heights or unstable footing.
Trail info: https://www.nps.gov/arch/planyourvisit/devilsgarden.htm

8) Wonderland Trail — Mount Rainier National Park, Washington
The Wonderland Trail is a 93-mile loop that circles Mount Rainier through some of the most spectacular alpine terrain in the country — and also some of its most hazardous. Glacial river crossings can swell rapidly and unpredictably as snow and ice melt throughout the day, weather can shift from sunny to whiteout conditions in a matter of hours, and the surrounding peak itself has one of the highest mountaineering death tolls of any mountain in America, driven largely by falls, rockfall, and sudden storms on technical climbing routes above the trail.

Time river crossings for early morning when glacial melt (and water levels) are lowest, and check current conditions before setting out.
Trail info: https://www.nps.gov/mora/planyourvisit/wonderland-trail.htm

9) Highline Trail & Grinnell Glacier Trail — Glacier National Park, Montana
Glacier National Park’s signature trails run along narrow, cliffside paths carved into mountainsides, often with steep drop-offs just a few feet from the tread. Add seasonal ice and snow that can linger well into summer, sudden weather changes typical of high alpine terrain, and one of the highest concentrations of grizzly bears in the Lower 48, and you have a setting where falls, slips on icy trail sections, and wildlife encounters all contribute to the park’s risk profile.

Carry bear spray, know how to use it, and check trail and weather conditions at a visitor center before setting out, since snow and ice can persist on shaded sections into midsummer.
Trail info: https://www.nps.gov/glac/planyourvisit/hiking.htm

10) Kīlauea Iki & Crater Rim Trails — Hawaiʻi Volcanoes National Park, Hawaii
Hiking near an active volcano comes with hazards you won’t find anywhere else in the park system. Trails around Kīlauea’s crater rim pass close to unstable cliff edges that can collapse without warning, and volcanic gases — including sulfur dioxide — can pool in low-lying areas and pose a serious respiratory hazard, especially for people with asthma or heart conditions. Eruptions and ground deformation can also close or reroute trails with little notice, so conditions here change faster than at almost any other park.

Always check current eruption status, air quality, and trail closures with the park before hiking, and never approach the crater rim past marked barriers.
Trail info: https://www.nps.gov/havo/planyourvisit/hiking.htm

A Note on the Numbers
It’s worth keeping these trails in perspective. National Park Service mortality data covering nearly two decades and billions of visits shows that national parks are, statistically, very safe places to be — most parks see fewer than one death per million visitors, and the leading causes of death system-wide are drowning, vehicle accidents, and medical emergencies rather than dramatic falls. The hikes above attract outsized attention precisely because they’re popular, scenic, and just risky enough that a single bad decision — pushing on through a storm, skipping water, leaning too far for a photo — can have serious consequences.

How to Hike Any of These Trails Safely
A few habits go a long way toward keeping any of these hikes in the “incredible memory” column instead of the “cautionary tale” column:

Check the official NPS trail page and current conditions before you go — weather, water flow, and trail closures change fast.
Start early, especially on exposed or high-heat trails, to avoid both afternoon storms and peak temperatures.
Carry more water than you think you need, and know the signs of heat exhaustion and dehydration.
Respect posted barriers and railings, particularly near waterfalls, cliff edges, and crater rims.
Tell someone your hiking plan and expected return time, and carry a satellite communicator in remote backcountry areas.
Know your own limits and turn back if conditions deteriorate — the summit or viewpoint will still be there next time.

National parks offer some of the most rewarding hiking on Earth. A little planning is usually the only thing standing between an unforgettable trip and a tragic headline