The National Park Service walks a tightrope, with two missions that often seem to be in conflict. Its first job is to preserve some of America's most unique and important natural areas for future generations; the second is to make these places available for the enjoyment of all Americans. Because the number of visitors to our national parks has grown tremendously over the years, some of the busiest parks, including the Grand Canyon, Yosemite, Zion, and Yellowstone, are constantly searching for ways to make both of these goals a reality.

Park Service officials have often said that the real source of congestion in the most heavily visited parks is not the number of people, but rather the number of cars. (You don't go to a national park to get caught in a traffic jam, do you?) As a result, those parks with yearly attendance in the millions are now putting together plans to limit vehicle traffic within their boundaries.

If all this leads you to despair that you can't have a true "wilderness" experience at a national park in the American West, banish the thought! Even in a park as crowded as Yosemite, there are places where you can completely escape the crowds, where you'll be able to walk among the trees and hear nothing but the sound of your own footsteps. All it takes is a little effort and planning, and that's where this guide can help.

Our authors have talked to the rangers, hiked the trails, and taken the tours, all the while asking, "How can our readers avoid the crowds?" Sure, if you're an outdoors ironman or woman you can avoid the crowds by taking off on the most strenuous backcountry hikes, but not everyone can manage that. So we've searched for secluded trails that can be hiked by the average person (not just the ones you see on the covers of Outside magazine), scenic drives where you won't get caught in bumper-to-bumper traffic, and points where, with only minimal effort, you'll be afforded spectacular views without feeling as if you're packed into Times Square on New Year's Eve.

We've also discovered that when you go is as important as where you go. Since most of the West's national parks and monuments are busiest in July and August, you can avoid many of the crowds by going in April or September, especially if you go just before students' summer vacation or just after classes resume. Most national parks are open year-round, though services are sometimes limited during the off season. In fact, many of the national parks are great places to go in winter for cross-country skiing and exploring, and you're less likely to feel mobbed. The hoodoos of Bryce Canyon, for example, are strikingly beautiful when they're capped with snow, and you won't be jostling with nearly as many people at the view points as you would in summer.

Another thing we've discovered (though it's not a big secret) is just how many hidden gems can be found among the national parks and monuments of the American West. Everyone knows about Mount Rainier and Carlsbad Caverns, but not always about the less-visited parks, such as Great Basin in Nevada, Great Sand Dunes in Colorado, the Channel Islands in California, Little Bighorn Battlefield in Montana, Jewel Cave in the Black Hills of South Dakota, and Guadalupe Mountains in Texas (which contains the highest peak in Texas). These are places of great beauty or historical significance, but they're often overlooked because of their remoteness or simply because they're relatively new to the national park system.

As we all explore these parks and monuments, we should remember that they have been set aside not only for our enjoyment, but also for future generations. Let our gift to tomorrow's park visitors be that we have almost no impact on the beauty around us and, if anything, we leave it cleaner than we found it.

In this guide, we give you the most useful general information you will need to help plan your trip to the national parks of the western United States.