National Park Roads Are Not Your Commute
The roads in national parks are beautiful and dangerous. Mountain passes with no guardrails, wildlife that materializes from darkness, rock slides that close highways for days, and winter conditions that turn scenic drives into survival situations. Every year, vehicles collide with wildlife, run off mountain roads, or get stranded in remote areas. Here's how to avoid becoming a statistic.
Wildlife on the Road — The #1 Hazard
Collisions with wildlife are the most common serious accident in national parks. An adult elk weighs 700 pounds. A bison weighs 2,000 pounds. Hitting either one at 45 mph will total your car and may kill you.
Where wildlife is most active:
- Dawn and dusk — animals are most active in the 2 hours around sunrise and sunset
- Yellowstone, Grand Teton, Rocky Mountain — elk, bison, and moose on roads in meadow areas
- Great Smoky Mountains — black bears and deer on Cades Cove Road and Newfound Gap Road
- Everglades — alligators and crocodiles on the road to Flamingo
- Acadia — deer on Park Loop Road, especially at dawn
- Drive 5-10 mph below the speed limit at dawn and dusk
- Scan the road edges, not just the center — animals stand at the tree line before entering the road
- Use high beams when no oncoming traffic is present
- Don't swerve — it's better to hit an animal than to go off a cliff. Brake firmly and stay in your lane.
- Watch for the second animal — deer and elk rarely travel alone
Mountain Roads — Respect the Elevation
Some of the most scenic drives in national parks are also the most demanding:
Going-to-the-Sun Road (Glacier): 50 miles, climbing to 6,646 feet. Vehicles over 21 feet long are prohibited. Rock fall closures common. Check current status before driving.
Trail Ridge Road (Rocky Mountain): The highest continuous paved road in the US, reaching 12,183 feet. Altitude sickness is real at this elevation — drink water constantly and pull over if you feel dizzy.
Tioga Road (Yosemite): 64 miles through the high country, reaching 9,945 feet. Closed November through May due to snow. Even in summer, carry warm clothes.
Zion-Mt. Carmel Tunnel: Vehicles over 11'4" require an escort ($15). The tunnel is 1.1 miles of unlit, narrow roadway with no shoulder.
Beartooth Highway (approach to Yellowstone): 68 miles reaching 10,947 feet. Not for the faint of heart — sheer drops, no guardrails, and weather that can change from sun to snow in minutes.
Mountain driving rules:
- Descending is harder than climbing. Use low gears, not brakes, to control speed on long descents. Riding your brakes causes them to overheat and fail.
- Pull over for faster traffic. It's the law in most park states. Use turnout lanes.
- Don't stop in the road for photos. Use designated pullouts. Stopping in a travel lane on a blind curve is a fatal mistake.
- Watch for cyclists — they have the same rights as vehicles on park roads
Weather Hazards
Flash floods: Desert parks (Zion, Death Valley, Canyonlands, Arches) are flash flood zones. A thunderstorm 20 miles upstream can send a wall of water through a slot canyon with no local rain. Check weather forecasts before entering canyons. The Narrows in Zion closes when flow exceeds 150 cfs.
Ice and snow: Mountain passes receive snow from September through June. Carry chains in your car from October through May. Check road status on NPS.gov before driving.
Dense fog: Great Smoky Mountains and Olympic are named for their fog. Reduce speed and use low beams (not high beams, which reflect fog back at you).
High winds: Desert and mountain parks can exceed 60 mph gusts. RVs and high-profile vehicles should pull over and wait it out.
Remote Road Essentials
Some park roads are 50+ miles from the nearest gas, cell service, or help. Pack these items for any remote drive:
- Full tank of gas — fill up before entering the park
- Emergency kit — jumper cables, tire inflator, basic tools, flashlight
- Extra water — 1 gallon per person per day if you're driving remote roads
- Paper maps — cell service is absent in most parks. Download Google Maps offline for the region
- Satellite communicator — for roads with zero cell coverage (Glacier, Yellowstone backcountry, Death Valley)
- Spare tire and jack — potholes and rock debris are common on park roads
Driving in RVs and Large Vehicles
- Know your height and length. Tunnel restrictions are strict and measured precisely.
- Use pullouts. You must pull over if 3+ vehicles are stacked behind you in several western states.
- Go slow on descents. Transmission in low gear, brakes for cornering only. Brake fade kills on mountain roads.
- Check park-specific restrictions before you go. Going-to-the-Sun Road bans vehicles over 21 feet. Zion-Mt. Carmel Tunnel requires escorts over 11'4". Many campground loops can't accommodate rigs over 30 feet.
Plan your road trip safely with our complete national park rankings.
Emergency Protocols
If you're in an accident or have a breakdown in a national park:
- Stay with your vehicle. It provides shelter and is easier for searchers to find than a person on foot.
- Call 911. Cell service is limited but sometimes reachable from higher elevations or near developed areas.
- Use your car's emergency features. Honk 3 times (SOS signal), flash your lights, and place a flag or bright cloth on your antenna.
- If someone needs immediate medical help and there's no cell service, send two people to the nearest developed area. One stays with the patient.
- Carry a satellite communicator — it's the only reliable way to call for help in the backcountry.