I had put off reading Cormac McCarthy's "All the Pretty Horses" for years, having picked it up when it first came out in paperback in 1993. But a Colorado vacation seemed a perfect time to take it up again. There's something satisfying about reading a book in sync with the locale where I happen to be.

Part of the book's appeal is simply that it is an adventure story, the tale of three young men -- boys, really -- who set off on horseback from west Texas in the late 1940s, seeking to recapture in Mexico a way of life fast disappearing north of the border. Instead they encounter a world so full of contradictions it destroys one of them, and nearly so the other two.

The Mexico McCarthy describes is a place of unspeakable cruelty, rigid convention and misplaced honor. It is a place where men can land in jail simply for being in the wrong place at the wrong time, and where obtaining justice depends on whom you know, not what you've done.

But it is also a country where the young men find incredible generosity and kindness -- poor Mexicans who are willing to share their meager food and abodes with strangers, even to give them, literally, the shirts off their backs. McCarthy's Mexicans are both villains and heroes, intellectuals and peasants.

But in the end, it isn't the adventure or the characters that makes this book so mesmerizing. It is McCarthy's ability to capture a sense of place.

The Southwest has for generations sparked the imagination of Americans. Even today, when skyscraper cities have sprung up on the plains where people make their living sitting at keyboards rather than on saddleback, the land itself remains wide-open, wild and vast.

The beauty of the land is stark, often harsh. There are few green, rolling hills, but jagged cliffs that jut out from the sage-covered brush, remnants of long-dead volcanoes, and earth the color of dried blood.

It does not look hospitable, which may be why it is so quintessentially American. Certainly in the early years, eking out a living in a land so arid made for an unimaginable challenge.

I think back on my own ancestors and wonder how they managed -- my father's family arriving more than 400 years ago in northern New Mexico from a similarly unforgiving landscape in Estremadura, Spain; my mother's family coming to Wyoming by wagon train from Missouri not long after the Civil War. Yet, like thousands of others, they tamed the land and recreated themselves.

Today, it is still possible to see in the land itself something of its past. Driving west along Route 40 high in the Colorado Rockies last week, I saw a herd of horses, some 40 or 50 head, that looked as if they had just descended, wild and free, from Byers Canyon above. There were overos, palominos, chestnuts and pure blacks, running against a classic Southwestern cerulean sky with cumulus clouds that dwarfed even the mountain ranges in the background.

There are few more enduring archetypes than the American cowboy. Certainly McCarthy's ability to conjure up a world in which men still ride on the backs of magnificent beasts trying to master a natural world that is both alluring and hostile has made him one of America's most popular literary figures.

But as the Southwestern landscape retreats, as suburbs encroach on the range, as fewer and fewer people know what it is to tackle nature head-on, what will happen to the cowboy tale? Perhaps this generation will be the last to come across boys like Jimmy Blevins or John Grady Cole or to see all the pretty horses running free, and all that will remain is a collective memory evoked by writers like Cormac McCarthy.