The river was wide, cloudy and flat, not what I’d expected of historic headwaters. Its banks were so thick with mud that I hesitated to wade in. But my husband was waiting in the stern, so I got in the bow without a word, and we pushed away from the landing.

As we glided into the main channel behind our guides and two other couples in canoes, I wondered why we had flown from the land of sky-blue waters to end up in a muddy Montana river in the middle of what looked — and felt — like a desert.

In just a few miles I had my answer.

And for the next three days, I had one of the best rides of my life.

Google “Missouri Breaks” and you’ll likely come up with the 1976 movie of the same name. Despite some serious starpower (Marlon Brando and Jack Nicholson), the movie was a dud. The real Missouri Breaks, while little known outside the region, are anything but.

Carved out of north central Montana’s high plains, the 149-mile stretch of river in the Upper Missouri River Breaks National Monument is made up of sagebrush-studded hills and deep coulees, towering cliffs that look as if they’d been built by ancient masons and massive rock walls that had been whittled by water, wind and time into eerie moonscapes.

My husband, Harold, and I had seen online photos of the changeable landscape. Still, we were blown away by the unearthly beauty and bend-by-bend surprises offered by this prehistoric playground.

Oddly enough, we’d ended up there almost by default. For years, we had backpacked and kayaked in the wilderness. Lately, though, we’d gotten a little too comfortable (re: lazy) to plan and pack, let alone make camp, break camp and actually hike or paddle. Since we’d been to the Montana mountains, we thought a river trip would be something completely different. It would also be a quickie (just three days), in canoes (which are easier to pack than kayaks) and guided. The guided part was a hurdle for us.

Being DIYers and admitted cheapskates, we’d never been on a guided wilderness trip. I didn’t like the idea of paying someone else to set up my tent or cook a camp meal, both of which I can do myself, thank you very much. Still, we took the plunge, signed up with Missouri River Outfitters in Fort Benton, Mont., and sent a deposit before we could change our minds.

As it turns out, the trip changed our minds. Having guides didn’t just make the trip easier. It made it more powerful, more memorable and a whole lot more fun.

Swimming holes and history

It was midmorning and already hot by the time we got to Coal Banks Landing, where we put in. I stood sweating and useless in the shade of a cottonwood while our guides — Nicolle Fugere and Danny Norris — piled gear into the 18-foot Old Town canoes. Lots of gear: wall tents, camp chairs, cots, coolers and roll-up tables. Watching them, I realized we weren’t going to be roughing it: This was glamping.

After a few instructions (C-stroke, J-stroke and have your life jacket handy), we set off on what turned out to be a floating lesson in topography, geography and a broad arc of history stretching from the great inland sea, to Lewis and Clark’s journeys, to when the steamboats were eclipsed by the railroads and the Missouri River lost its role as gateway to the west.

Nicolle and Danny, open and outdoorsy Montana natives, were never pedantic or boring, but they knew their river and its storied past. And in the Breaks, that past is very much present. What we were seeing was a slice of the 375,000 unspoiled acres that had enthralled plains Indians, explorers, trappers, traders, settlers and outlaws.

For the first couple of hours on the river (which was cleaner and swifter than it first looked), we paddled easily through the kind of rough, ragged landscape you see in old westerns, only without the cowboy silhouettes. But even before we stopped for lunch, the land started to rise and fall.

Then, we entered the White Cliffs — sheer walls of white sandstone rising as high as 300 feet straight up from the river bed. It was so stunning that I stowed my paddle to watch the formations slip by. From the bow of his canoe, Danny explained to us how they’d been made: Over millions of years, the river had cut down through the soft rock. To me, they looked like ruins — castles, cathedrals, statues — of some ancient civilization.

After a lunch, the heat grew oppressive, so Nicolle offered to take us to her favorite swimming spot. We followed as she beached her canoe, donned her life vest and walked to where a steep cliff met the water — and kept walking.

What she knew — what we couldn’t see — was that there was a stone ledge about a foot underwater, which formed a narrow sidewalk. We walked upstream until the ledge stopped, then jumped in the surprisingly chilly water with a “whoop!” and let the current carry us down. Even though we cooled off fast, we kept jumping in and riding down, one after the other, like little ducklings.

It wasn’t far to Eagle Creek, where we would camp for the night. As soon as we landed, Nicolle and Danny broke out the coolers and the snacks while we chugged cold mineral water and beer, changed out of our wet clothes and laced up our boots for our next adventure — a hike up a slot canyon.

Once again, our guides added to the adventure. We crossed the grasslands on a narrow footpath and entered a canyon, which thankfully offered shade. We followed a twisting dry stream bed as the canyon walls narrowed, steepened and ended in a rock pile. Instead of turning back, Danny showed us how to slip around the rocks so we could climb to the top of the canyon — a treeless, rock-strewn plateau that gave us an interrupted view of the bizarre rock formations that surrounded us.

After dinner we sat around the campfire, too tired, too relaxed to play the word games Danny suggested. So Nicolle pulled a book from her “river library.” It contained an 1805 piece by Meriwether Lewis describing the White Cliffs. He wrote of “the remains or ruins of eligant buildings,” and “vast ranges of walls of tolerable workmanship, so perfect indeed that I should have thought that nature had attempted herre to rival the human art of masonry.” Clearly, Lewis and I thought alike.

In our tent, with a cool breeze finally coming through the screens, I dozed off, marveling about how the Breaks were able to erase 210 years of time.

Guiding our footsteps

After breakfast (camp-style Egg McMuffins), we took a history hike — a short walk up to a low rise with several circles of large rocks poking out of the ground. Nicolle explained that these tent circles or tepee rings were left by plains Indians, most likely Blackfoot, who were once prominent in the area. She looked down at the wide, bending river and wondered aloud how the tribe must have felt when it saw the first steamboat belching its way up the river. Then she led us to some petroglyphs, delicate images of horses carved into cliff walls.

Our second day on the river was easily as fun as the first, if longer. We paddled, chatting comfortably between the boats, until we pulled off for lunch. There was a small grove of cottonwoods for shade and a unique rock formation for adventure. “See that?” Nicolle asked, pointing up hundreds of feet. “That’s Hole in the Wall. We’re going to climb it.”

I laughed until I realized she was serious. But with her and Danny’s help, all six of us made it to the top. (Two of the campers even crawled through the “hole.” I chickened out.)

Getting to the top wasn’t all that hard. Getting down wasn’t going to be easy. There were several short vertical rock faces we had to clamber down. Nicolle and Danny talked us down, telling us where to grab onto the rock, how far down the next foothold was. In a few places, they even held onto our hiking boots so we wouldn’t slip. I’d never been on as challenging a hike and felt as safe as I did then.

When we got back on the river, it was fairly late. The campsite we had planned to hit was crowded, so we paddled on to a makeshift campsite the guides knew. There, we sat in the river, cooling off and waiting for dinner.

Breaking the spell

Since we were only paddling part of the Breaks, our last day on the river was short and easy. We stopped to see a prairie dog town just a short hike from the banks. Back on the water, Nicolle suggested we raft up. So we maneuvered our boats together, and settled back and let the river carry us.

For a while, we drifted silently, listening to the distinct, sparse sounds of the wilderness — the caw of a magpie, the low of a calf upstream, the rush of small, shallow rapids. Someone asked Nicolle if she would read, so she pulled out a slightly soggy copy of Stephen Ambrose’s “Undaunted Courage,” a chronicle of Lewis and Clark’s journey, and started reading.

Her clear, even voice floated over us like a benediction. I tried to remember each word — just as I had tried to memorize the shapes carved out of the cliffs, twists of the canyons, the smell of the sage — but I couldn’t catch them all.

I remember that Ambrose was musing about Lewis’ troubled decline and death. Had Lewis been thinking about his many failures, Ambrose wondered, or had he been looking west, toward all the majesty he’d seen, the wondrous new world he’d help chart?

I was hot, tired, bug-bitten and in a state of bliss. I wanted to stay here, in the middle of this odd and rugged landscape, floating between the past and the present.

I heard a strange sound — was that a car? — and turned to look downstream. There was a bridge, the first we’d seen. It marked our take-out point.

Nicolle closed the book. Danny started to give instructions on how to approach the landing. We all sat up and slowly, reluctantly picked up our paddles. I was hesitant to leave this muddy, magical river. I, too, kept looking west.