This is what the last straw looks like: a parade of Harleys and their leather-clad riders rolling past the granite monoliths and spiky plants of California's Joshua Tree National Park. After a morning of sharing the high desert with youth groups and retirees, the bikers' bleating chrome exhausts seemed a sad confirmation that the solitude we seek in wild places is nowhere to be found in the national parks. Or is it? I parked my car, shouldered my pack, and left the pavement behind. I hiked until the sun dipped below the horizon and pitched my tent on a patch of sand, creosote, and juniper—just me and the emptiness and my sputtering camp stove. The next morning, after scrambling up a nearby ridge, past jackrabbit and coyote tracks, I stared down at the wide valley a thousand feet below, feeling like the master of all I surveyed—which, as a taxpayer, I sort of was.

Remarkably, fewer of our fellow taxpayers have been enjoying America's national parks. Total visits to the park system—more than 84 million acres spread over nearly 400 parks and monuments—numbered 272 million in 2006, down from 287 million in 1999. But fewer visitors means more park for the rest of us. And since most patrons rarely stray more than a doughnut's throw from their minivans, people like us—as I discovered at Joshua Tree—can usually have the backcountry to ourselves for the price of a little sweat.

Where to begin? We polled national-park experts for their secret stashes, the places they go to escape the masses. But there's just so much we can do. As John Muir wrote in his 1901 book Our National Parks, "To defrauded town toilers, parks in magazine articles are like pictures of bread to the hungry. I can write only hints to incite good wanderers to come to the feast." The feast awaits—still.