Tucked away where northwestern Colorado and northeastern Utah converge, Dinosaur National Monument is a remote, oft-overlooked place. Indeed, during 2006 just 278,473 people made their way to the monument, which preserves a rich and fascinating slice of prehistory.

The monument also played a pivotal role in water management in the Southwest, a role that "touched the heart of the National Park Service by threatening its basic mandate to protect individual parks and the integrity of the entire system." The fight against a proposal to build a dam (as well as a sprawling resort) near the confluence of the Green and Yampa rivers that meet at Echo Park within the monument was taken up by none other than David Brower, who in hindsight erred by agreeing not to oppose the Glen Canyon Dam downstream in order to save Dinosaur.

But that's another story.

What writer Hal Crimmel and photographer Steve Gaffney present to us in Dinosaur, Four Seasons on the Green and Yampa Rivers, is a stirring portrait of the landscape that is Dinosaur. Mr. Crimmel comes to this collaboration with both a lengthy resume as a river runner and a naturalist's eye, while Mr. Gaffney captures the varied breadth, as well as tightly focused vignettes, of the monument with his camera.

Together they've created a work that blends history with interpretation, river running with quiet introspection. They've given depth to this unit of the national park system that has struggled in recent years due to inadequate funding and lack of attention by the National Park Service.

The sun sinks below the canyon rim. We navigate disorderly, braided, sandbar-strewn channels that give Mitten Park a wild feel. Shadowy spires and fins of uplifted rock sweep around a warped outcropping at the mouth of Whirlpool Canyon. Farther in, we crane our necks upward to view sea stacks a half-billion years old that are evidence of ancient surf thundering against a rocky coast. Sea stacks are islands found near coastal areas, formed when headlands erode. As the ocean advances, softer formations erode, leaving harder vertical columns of rock standing offshore. Visible along the Oregon coast, for example, sea stacks are found throughout the world and time. Whirlpool Canyon's sea stacks are a visible reminder of the marine origins of Dinosaur's canyons.

In the book's 78 pages, the two not only examine the Green and Yampa rivers that crisscross Dinosaur, the mountains that rise up within it, and the canyons that are cut into the landscape, but they also explore its continued existence in an industrial environment that places more value on oil and gas development in this nook of the country than in rivers that jump and weave.

In 1938 the federal government expanded Dinosaur to 203,885 acres in Utah and Colorado; in 1960 the monument was enlarged to its present 211,141 acres. Many wilderness groups would like to have another 120,000 acres added to the monument in order to protect surrounding lands. This nearby desert shrub country can lack the picturesque features that typically help garner support for federal protection, but places such as Bull Canyon, Cold Springs Mountain, archaeologically significant Daniels Canyon, and Diamond Breaks are necessary for maintaining Dinosaur's wild essence. Among other advantages, adding these places to the monument would further protect the watershed and preserve vistas from oil and gas development. Wildlife would benefit too. Predators such as mountain lions and bobcats and ungulates such as Rocky Mountain bighorn, elk, and mule deer would have greater room to roam. Yet regional opposition to monument expansion is strong. In a movement similar to the anti-federal, anti-environmental sentiments of the 1970s Sagebrush Rebellion, counties adjacent to the monument and throughout the West are turning to a Civil War-era right-of-way law in order to foil expansion of wilderness areas and fragment lands managed by the Park Service.

It's just that sort of environment that requires more books such as this one. Books that clearly express why the landscape in question is not just so dear and magical, but also vital for our existence.