The best place to start is where the river makes its first delicate incision into the stony lands south of Green River, Utah. Downstream of teapot-shaped Dellenbaugh Butte, thicker sandstones rear up from the ground, and Canyonlands begins.

This is where I began, too, in the 1980s, a scrawny kid in his late teens working for a fly-by-night canoe outfit. My mom was dating the owner, which is how I got the job running trips around the Intermountain West on the North Platte, Yampa, Gunnison and Colorado rivers. I was supposed to convince clients I knew what I was doing even though I had never seen most of these rivers before. When a 10-person trip on the Green River into Utah's Canyonlands came up, some of it through Canyonlands National Park, some through surrounding Bureau of Land Management holdings, my mom's boyfriend put me on it.

The Green River is born far north of here in the Wind River Range of Wyoming, and briefly halts at the sediment trap of Flaming Gorge Dam. South of I-70 in Utah, it carves into an arid warren of sandstone canyons. Eventually, it meets the Colorado River, and their confluence forms a V in the center of Canyonlands, drawing a perfect tail of a heart.

I'd never seen anything like it. The clients raged at me for forgetting to bring coffee. What did it matter? I was falling in love.

Growing up, I had preferred the edges of the playground to the mania of foursquare and tetherball. I was a reflective only child, and human interactions and relationships seemed too fleeting to count on. Maybe it was because we moved so often, back and forth between Arizona and Colorado. But rocks and dirt -- and the landscapes they built -- were something I could depend on. They offered a sense of permanence and stability, even though in the scale of geologic time, I knew they were anything but. The Southern Rockies and their descending layers of desert were burned into my head. Now, I carried this connection a step farther, following the placid, mud-swirled Green deeper into this eroded country.

One day, I hiked up a side canyon with my clients. We weren't on a trail, and for all I knew, we were heading straight into a dead end. But through notches and over boulder-aprons, the sandstone kept opening and opening again. We could see into tower-capped canyons and alcoves. There were a few maidenhair fern-draped seeps, but everything else was nearly naked of vegetation and painted in dazzling shades of red. I began jogging. The clients shouted at me, and I called for them to follow. I ran faster, scrambled higher, and finally reached the top of a knoll that felt like the center of an enormous compass.

The few clients who hadn't turned back caught up with me, out of breath and smiling. Where were we? they wondered. What had we come to see?

I waved my arm across the arterial mass of buttes and canyons all around us. "We're here," I said. "We've found it!"

Not all maps are made of paper. The best ones are spooled in memory, better served by songs and stories than by something that lays flat in a drawer or glows on a computer screen. The map that I've been making -- as diligently as a monk in a stone scriptorium -- is of Canyonlands. The national park takes up 337,570 acres, surrounded by a hefty perimeter of 1.4 million acres of BLM known as Greater Canyonlands. It lies west of Moab, south of the Book Cliffs, east of the San Rafael Swell, and north of Lake Powell.

At first, I carried topographic maps of the region. Folded with corners soft as cotton, I kept them stuffed in my pack. At home, I pored over them, covered floors with them, my imagination tracking their possibilities.

By the time I graduated from college, I traveled to Canyonlands often, running half-naked through slickrock fins, returning July, October, January. I wanted to understand the place. I counted ants and shadows, summering in caves, waiting for the intense and odorless heat to die before venturing farther. On the river, both the Green and Colorado, I went alone and drifted on my back, a bowline tied to me so my boat and I would not float apart. Canyon walls opened and closed gently, big blocks of 500-foot-tall sandstone cleaved like chunks of cherry-red chocolate. When I shouted, my echoes came back like snowflakes, never the same.

As I entered my 30s, my obsession grew. I couldn't get enough, going out for weeks. My friends were those who did the same. The dotted lines that defined borders and trails meant nothing to us. We did not recognize where national park became BLM. What we saw was an interlocking network of contours and notches and climbs and ways to slip through.

We had our own place names. Dead Guy is what we called one route, after a complete human skeleton in a natural rock shelter near the top of a steep, boulder-filled drainage. Bereft of skin or fabric, its bones were half-buried in dust. The person had either died or been interred there centuries earlier. We didn't mess with the skeleton or mark it on a topo with an X. It was a mental juncture for us, a reference. We'd say, Let's meet at the Dead Guy.