Bears, rattlesnakes, and lightning can be dangerous, but that driver heading for you on a park road can be even more dangerous. In fact, motor vehicle accidents cause more deaths in the parks every year than anything else. Scenic drives are often winding and steep; take them slowly and carefully. And no matter how stunning the snowcapped peak you may glimpse is, keep your eyes on the road.

When out on the trails, even for a day hike, keep safety in mind. The wild, untouched nature of these parks is what makes them so exciting and breathtakingly beautiful -- but along with wildness comes risk. The national parks are neither playgrounds nor zoos. The animals here are truly wild and sometimes dangerous. This doesn't mean that disaster could strike at any time, but visitors should exercise basic caution and common sense at all times, respecting the wilderness around them and always following the rules of the park.

Never feed, bother, or approach animals. Even the smallest among them can carry harmful, sometimes deadly, diseases, and feeding them is dangerous not only to you, but also to the animals, who (like us) will eat what their bodies can't handle. In addition, wild animals' dependence on handouts can lead to unpleasant confrontations, which often result in rangers having to relocate or kill the animal. As the Park Service reminds us, "A fed bear is a dead bear."

In some parks where there are bears and mountain lions, it's often a good idea to make noise as you hike, to make sure you don't stumble upon and frighten an animal into aggression. Also, follow park rules on food storage when in bear country. Photographers should always keep a safe distance when taking pictures of wildlife -- the best photos are shot with a telephoto lens.

It's equally important for your safety to know your limitations, to understand the environment, and to take the proper equipment when exploring the park. Always stop at the visitor center before you set out on a hike. Park staff there can offer advice on your hiking plans and supply you with pamphlets, maps, and information on weather conditions or any dangers, such as bear activity or flash flood possibilities on canyon hikes. Once out on the trail, hikers should always carry sufficient water and, just as important, remember to drink it. Wear sturdy shoes with good ankle support and rock-gripping soles. Keep a close eye on children in your group, and never let them run ahead (especially in bear or mountain lion country).

Since many park visitors live at or near sea level, one of the most common health hazards is altitude sickness, caused by the high elevations of many of the parks in this guide. Symptoms include headache, fatigue, nausea, loss of appetite, muscle pain, and lightheadedness. Doctors recommend that until you are acclimated -- which can take several days -- you should consume light meals and drink lots of liquids, avoiding those with caffeine or alcohol. It's a good idea to take frequent sips of water as well.

One proven method of minimizing the effects of high altitudes is to work up to them. For instance, on a visit to southern Utah, go to lower-elevation Zion National Park for a day or two before heading to the higher mountains of Bryce Canyon. Those concerned about altitude sickness might also consult with their doctors before leaving home; there are drugs that can be taken beforehand that may minimize the risk.

A waterborne hazard is Giardia, a parasite that wreaks havoc on the human digestive system. If you pick up this pesky hanger-on, it may accompany you on your trip home. The best solution is to carry all the water you'll need (usually a gallon a day). If you need additional water from the parks' lakes and streams, it should be boiled for 3 to 6 minutes before consumption.

Health experts also warn outdoor enthusiasts to take precautions against hantavirus, a rare but often fatal respiratory disease, first recognized in 1993. About half of the country's confirmed cases have been reported in the Four Corners states of Colorado, New Mexico, Arizona, and Utah. The droppings and urine of rodents usually spread the disease, and health officials recommend that campers and hikers avoid areas with signs of rodent occupation. Symptoms of hantavirus are similar to flu, and lead to breathing difficulties and shock.

Hiking Tips

Don't venture off on any extensive hike, even a day hike, without the following gear: a compass, a topographical map, bug repellent, a whistle, a watch, and sufficient water. In many western parks, sunglasses, sunscreen, and wide-brimmed hats are also considered essential. To be on the safe side, you should keep a first-aid kit in your car or luggage and have it handy when hiking. At a minimum, it should contain butterfly bandages, sterile gauze pads, adhesive tape, antibiotic ointment, pain relievers, alcohol pads, and a knife with scissors and tweezers (tweezers are especially useful for removing those nasty little cactus spines that seem to attack from the side of the trail). In many national parks, cellphone service is spotty or nonexistent, so don't depend on being able to call for help in an emergency unless you have a satellite phone (which is rather expensive to own but can be rented for your stay in a remote area).

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.