(MONEY Magazine) – People sometimes ask me, "What's your favorite road trip?" There's no singularly definitive American road trip, of course--it's too big a country for that--but there's a scenic byway that comes close: the Great River Road. Established by the Department of the Interior in 1938, the GRR is a network of state and local highways--or rather two parallel networks, one on each side of the river--running along the Mississippi River's full length. White signs with a green steamboat pilot's wheel logo mark the GRR route, which is overseen by the Mississippi River Parkway Commission in Minneapolis.

Why is the GRR such a great trip? For starters, the Mississippi River is firmly embedded in American history and lore. With a drainage basin stretching from Montana to upstate New York, it's also one of the mightiest rivers on earth. Once considered the country's western border, it's now more of a de facto signpost marking the nation's cultural midpoint, as well as a crucial artery for commerce and irrigation. The river--and therefore the GRR--passes through an extraordinarily broad range of sights and attractions, from major cities to flyspeck towns, from Civil War battlefields to historic settlements, from agriculture to industry. And while any lengthy road trip is bound to entail a diverse cross section of American culture, north-south routes like the GRR are particularly good in this regard because America's regional cultures tend to cleave more starkly from north to south than they do from east to west.

My friend David and I set out to drive the 2,000-mile length of the GRR last September. But the Mississippi's source is in remote north-central Minnesota--an inconvenient starting point--so we cheated a bit and began in Minneapolis, giving ourselves nine days to get to New Orleans. Although the GRR passes through major cities like St. Louis and Memphis, we agreed to bypass urban centers as much as possible and stick with the sticks, in part because cities would be too time consuming and in part because we wanted to see what was left of small-town America before it got completely swallowed up by Wal-Mart. From time to time we referred to guidebooks, but there were also long stretches of the drive when we just stopped whenever something caught our eye.

It's worth noting that the following travelogue represents only a fraction of what we would have done if we'd had more time. To really appreciate the GRR's full length, I'd allocate a good three weeks or so. On the other hand, there's no need to drive the entire GRR--any subsection of it is a worthy trip in its own right. You can construct any number of different itineraries. Start by contacting the Mississippi River Parkway Commission (763-212-2560; www.mississippiriverinfo.com), which can supply you with maps, brochures and information on the GRR and the 10 states it passes through. For guidebook suggestions and other useful resources, see the box on page 188.

Finally, you may notice that the river itself doesn't figure too prominently in our adventure. That's because while parts of the road run right alongside the Mississippi, there are also large sections that run a few miles inland, especially as you head farther south, where the Mississippi's increasingly serpentine path has made riverside highways impractical. High levees sometimes obscure the river from view as well. But there's always the sense that the river is close by, like an unseen companion, and the GRR always leads back to its banks eventually. Follow the pilot's wheel signs, and you'll have quite an odyssey. Here are some highlights from ours.

Day One: We fly to Minneapolis, rent a car and begin driving south, occasionally crossing from Minnesota to Wisconsin and back again as bridges present themselves. The riverscape vistas are spectacular, but the afternoon's big surprise comes in Winona, Minn., where we spot the Merchants National Bank (102 E. Third St.; 507-457-1100), designed by William Purcell and George Elmslie--contemporaries of Frank Lloyd Wright. With its stained-glass windows, terra cotta details and huge interior mural depicting a pastoral farmland scene, it's easily the coolest-looking bank we've ever seen. The day concludes shortly thereafter at idyllic Perrot State Park in Trempealeau, Wis. (608-534-6409), where a nap in a sunny riverside meadow provides the perfect capper to a long day of flying and driving.

Day Two: We rent bicycles in Trempealeau and spend the morning biking along the Great River State Trail, a defunct railroad corridor that's been converted into a trailway. The route cuts through a wildlife refuge, where the marshy environs are crawling with turtles. Then we drive south into northeastern Iowa and visit the fascinating Effigy Mounds National Monument (151 Hwy. 76, Harpers Ferry, Iowa; 563-873-3491; www.nps.gov/efmo), which features dozens of prehistoric Indian burial mounds, many shaped like bears and eagles (and once mistakenly thought to have been created by an alien race). The mounds are beautiful and affecting, but our contemplative mood is short-lived, for a little while later we stop for the evening in Dubuque. The city unexpectedly turns out to be one of the greatest neon-sign towns we have ever seen, with hotels, restaurants, bars, car washes and even plumbing storefronts all wonderfully, classically aglow.

Day Three: A very farm-beltish day, with two quintessentially midwestern experiences. First, in tiny Bellevue, Iowa, we stumble across the town's annual pig roast, complete with music, raffles, auctions and numerous reminders that Iowa is America's top hog-farming state. It's Sunday, and people are literally streaming out of a nearby church and directly on to the pork sandwich line--an amazing scene. The civic spirit is palpable and the pork is dee-lish. Next stop: Moline, Ill., where we visit the corporate headquarters of John Deere (1 John Deere Place; 309-765-8000), whose tractors and combines are staples of the farmland we've been traversing. There's a huge public showroom filled with Deere products--not just farm equipment but also bulldozers, backhoes, forklifts and excavators. We're allowed to climb up and sit in most of them, and that's exactly what we do, like kids who've been turned loose with a set of full-size Tonka toys.

Day Four: Today we focus largely on two historic Americans, beginning in Nauvoo, Ill. It was here that the Mormon prophet Joseph Smith and his followers settled in 1839. In 1846, two years after Smith was killed, the Mormons fled Nauvoo for Utah. Today the town has been restored as a living museum--sort of a Colonial Williamsburg of Mormonism--and we get a thorough grounding in the movement's history as we tour the village. A less satisfying encounter comes later on in Mark Twain's boyhood home of Hannibal, Mo., where rampant Disneyfication (virtually every business in town is named after Twain or Tom Sawyer or Huck Finn) has overwhelmed any serious consideration of Twain's literary importance. Fortunately, an antidote to this theme parkery comes in the evening, when a beautiful car ferry ride at sunset provides our most intimate encounter with the river and restores our good mood.

Day Five: Riverboat gambling has so proliferated along the Mississippi that no point on the GRR is more than 100 miles from a casino. We get considerably closer than that today, as we spend the morning gambling in Alton, Ill. The blackjack gods are with us, and we both clear a slight profit. Next we stop at two very different monuments: the Gateway Arch in St. Louis (877-982-1410; www.gatewayarch.com) and the World's Largest Catsup Bottle in Collinsville, Ill. (618-345-5598; www.catsupbottle.com), each one deservedly a tourist mecca in its own way. But the day is ultimately defined by a gorgeous afternoon driving on picture-perfect country roads through lower Illinois, with the river on our right and spectacular limestone bluffs looming to our left. We end up at the state's southern tip, poised to enter the South.

Day Six: We leave Illinois and meander through western Kentucky and Tennessee, passing at one point through Columbus, Ky., which was briefly under consideration to be the nation's capital after the War of 1812. The transition from the Midwest to the South is striking: The landscape, which until now has been punctuated by rolling hills, becomes almost completely flat; burger joints are replaced by barbecue shacks; fields of corn give way to cotton; after days of seeing nothing but white people, we now see African Americans; billboards spout Christian messages; and the roads have names like the Carl Perkins Parkway. With no major attractions on today's agenda, we spend the afternoon stopping at various small-town shops, happening upon a major discovery in Halls, Tenn.: Murray Hudson, an astonishingly well-stocked antiquarian book and map store (109 S. Church St.; 800-748-9946; www.murrayhudson.com), whose presence in this isolated rural outpost seems wholly impossible. We scour every inch of it and then silently drive on, basking in that shared feeling of having experienced something special.

Day Seven: We enter the Mississippi Delta, where our day centers on two elderly gentlemen. First, at the Delta Cultural Center in Helena, Ark., we watch venerable 74-year-old deejay "Sunshine" Sonny Payne as he delivers his 13,826th edition of the King Biscuit Time blues radio show, which he broadcasts live and in public view each day (141 Cherry St.; 800-358-0972; www.deltaculturalcenter.com). His spirit and energy are irresistible, and so is his invitation to chat on the air with him--a particular thrill for me, a longtime blues fan.

But an even more remarkable encounter awaits us later in the destitute-looking town of Alligator, Miss. (pop. 187), where we're amazed to find the Whale Store, an old-fashioned dry goods shop whose dusty selection of shirts, housecoats, children's shoes, sewing notions, patent oils, neckties, cosmetics and fedoras appears to have been frozen in the early 1960s. This place is even more implausible than Murray Hudson, and more incredible still is its proprietor: Aaron Kline, a chatterboxing, nonagenarian Lithuanian who's been running the joint since 1937. We're his only customers of the day (or maybe the month), so he happily talks our ears off about history, geopolitics and the decline of public morals. "There's always change," he says. "Some for the good, some for the bad." Maybe so, but here's hoping nothing changes in his shop for at least a little longer.

Day Eight: Today we pursue folk art, beginning in Vicksburg, Miss. with a stop at Margaret's Grocery, a former corner store that's been converted into an ad hoc temple run by 85-year-old Rev. H.D. Dennis (4535 N. Washington St.; 601-638-1163). It's an incredible place. The exterior is a carnival of multicolored cinderblocks and hand-painted signage extending every which way, and inside there's an endless clutter of homemade shrines and displays that Rev. Dennis has created from beads, Christmas lights, stuffed animals, tinsel, crepe paper, plastic flowers, pompoms, prayer books and wicker baskets ("All because God told me to," he explains). The site approaches sensory overload, especially when the good reverend starts philosophizing--the man has no off switch. We finally excuse ourselves and head slightly east to the small town of Bovina, where we visit Earl Simmons, a rural carpenter whose ramshackle home is also a gallery for his primitivist paintings and sculptures (6444 Warrior Trail; 601-638-4635). The scene is a bit surreal--the house feels like it's held together with staples, and Earl's kids scamper around barefoot. David eventually buys a painting and then we briefly leave the GRR to drive along the Natchez Trace Parkway, a scenic two-lane byway running along an old Indian footpath extending from Natchez, Miss., to Nashville. A 200-yard tree-canopied section of the old Trace itself has been preserved near the roadway, and we stop to walk its length, imagining what it must have been like to traverse the entire 450-mile route back in the days before the white man arrived.

Day Nine: Our last day on the road brings us to Vacherie, La., where we visit Oak Alley, considered by many to be the quintessential southern plantation (3645 Hwy. 18; 800-442-5539; www.oakalley plantation.com). The plantation house tour features the usual assortment of Victorian furniture and the usual failure to mention the slave labor that once made the place run. But the titular corridor of massive oak trees, planted in the 1700s and now covered with kudzu, is spectacular enough to justify the trip. From there it's a short jaunt to New Orleans, where we drop off the car and prepare to fly home. Our final tallies: 10 states, about 2,000 miles and a handful of characters we'll never forget. Maybe not the perfect road trip, but it'll certainly do until something better comes along.