Proof on Main, Louisville's restaurant of the moment, laid out the options squarely. I could surrender my appetite to Tuscan-themed gourmet treats such as green beans with San Marzano tomatoes and yellowtail fish with picholine olives. Or I could build a meal around cheese-filled Kentucky grits, country ham fritters and other Southern standbys.

I paused and, like a tourist fidgeting with a map, surveyed the plates around the dining room. Did I prefer my Louisville with a twist or straight up?

During my long weekend sojourn through this Kentucky river city last month, I met this question at nearly every turn.

Kentucky's biggest urban area, an expanse of grand residences and plain brick factories stretched along the Ohio River, has two starkly different scenes. There's traditional Louisville, home to a collection of American classics: Churchill Downs, the country's ruling stronghold of horse racing. The Old Seelbach Bar, a handsome swath of mahogany that offers so many brands of vintage bourbon you could sip a new one every week for a year. The Louisville Slugger Museum & Factory, producer of baseball bats since the 1880s. Old Louisville, an elegant neighborhood lined with hundreds of Queen Anne, Colonial and Gothic Revival and chateauesque mansions, extending over 45 quaint square blocks just south of the central business district.

Then there's downtown. Fresh from a spree of urban renewal akin to a spiked-hair makeover, it's an enclave of eclectic museums, fine dining and hip watering holes. Stage buffs hang in these streets, especially at the Actors Theatre, which features both classic and wildly avant-garde works. (Talk about avant-garde: A young artist recently spent three weeks on exhibit in a glass cubicle in a busy Main Street restaurant.) And the area's Muhammad Ali Center — look for the contemporary building with the roof shaped like a butterfly — opened last fall as a monument to a Louisville favorite son.

So which would it be: With a twist, or straight up?

Louisvillians typically sample a side dish of New Age with heaping portions of tradition. The city and surrounding Jefferson County, a motley conglomeration of neighborhoods spread over a large area, are not easy to typecast. The city — a half-day's drive to Chicago and not much farther to Atlanta — sits squarely on the divide between the South and the Midwest. The 700,000 inhabitants (including the city proper and Jefferson County) are a colorful mix of unlikely groups: landed gentry, tobacco farmers and factory hands, Jews, Catholics and Baptists, whites and blacks.

Downtown along West Main Street, between First and 10th, revitalized Louisville is on display. Block after picturesque block, the broad boulevard is lined with dozens of 19th-century buildings constructed of cast iron and originally used as warehouses for tobacco and other goods. Recently restored, they're now residential lofts, restaurants and cafes. Picture a quieter version of New York's SoHo.

If the heroes of a place are any measure, Louisville is about as quirky and high-spirited as American cities come. You can see this city's stars painted across the sides of downtown skyscrapers: Col. Harlan Sanders of Kentucky Fried Chicken fame, sporting his trademark white suit; Pat Day, jockey extraordinaire, captured in the exuberant moment when he won the 1992 Kentucky Derby; "Good Morning America" host Diane Sawyer, exuding the same confidence she offers TV viewers; and Ali, flashing his familiar elfish grin. All four spent pivotal stages of their careers in Louisville.

A few blocks away, in the edgy 21c Museum Hotel, I ran into my first downtown Louisvillian, Lauren Argo. The Lexington, Ky., artist who lived for weeks in an enclosed window space in the hotel's restaurant was working on a piece in a side gallery of the modern art museum in the lobby.

"I guess people didn't expect to see that kind of thing in Louisville," said the giggly blonde, referring to her show. "But why not? Cities change. They don't always live in the past."

Steve Wilson, who owns 21c with his wife, Laura Lee Brown, was the second. The couple have been key players in the revival of downtown. "Louisville has a tradition of upholding tradition," he said. "Now we're trying to bring another dimension to all that."

Talk of changing the culture was my cue to head down West Main and around the corner to the Ali Center. Open since last November, it makes great use of high-tech video presentations and interactive displays about the boxer's life, passions and principles.

A powerful introductory film tells how Cassius Clay, during his childhood and adolescence in this city's predominantly black West End, took up boxing and began reciting wisecracking poems, twin passions that would follow him through life. Using a replica of his rustic training camp in Deer Lake, Pa., as a backdrop, the film explains how the driven young athlete combined thought and brawn to develop his unique approach. Afterward, visitors can get a mini-lesson on how to tangle with a punching bag.

Many of the biographical details will be familiar to Ali fans: his conversion to Islam, his outspoken civil-rights advocacy, his refusal to be drafted for the Vietnam War. One display details the six principles of Ali's life: respect, confidence, conviction, dedication, spirituality and giving. Other exhibits detail his humanitarian missions and his public battle with Parkinson's disease.

Was a stay in Louisville possible without a trip to Churchill Downs? Apparently Louisvillians don't think so. The 131-year-old track may be best known as the site of May's vaunted Kentucky Derby, but it hosts regular horse racing in season (late April to July 4 and during November). When I arrived on a slow Saturday, a crowd was already cheering on a field of horses.

A novice to this sport, I headed first for a "backside tour," offered by the neighboring Derby Museum. The one-hour guided van excursion went to the barns where the horses live and where hundreds of trainers, handlers and riders are at work trying to groom a new Secretariat, the beloved Kentucky Derby champion. A guide offered tidbits on the value of dozens of horses (ranging from $30,000 to $500,000), on how the horses are fed and cared for, and how, upon death, the bodies usually are cremated — but the head, heart and hooves are buried.

Even in midsummer, the Churchill Downs complex, expanded last year to include a total of 1.4 million square feet, had an air of festivity and ritual. The stadium, which can hold just under 52,000 spectators, was a third full. Yet everyone — bettors next to onlookers, young couples in jeans aside old codgers in fishing hats and dark glasses — was up on their feet, letting go a roar as the horses thundered past.

Besides fine horses, this region also produces the lion's share of the world's bourbon. A string of major distilleries (led by Jim Beam, Maker's Mark, Wild Turkey, Four Roses and Heaven Hill) are within a 90-minute drive of downtown, an easy excursion. I chose Maker's Mark, set on 630 bucolic acres in the village of Loretto, about 58 miles south of downtown. It's one of the smallest and most intimate and exclusive of the distilleries.

Back in Louisville for dinner that night, I settled into the tony Proof on Main. I still had a choice to make.

Eventually, I decided to straddle the city's two cultures with a side order of grits and a main course of striped bass with stewed artichokes and marinated tomatoes. And my bourbon? With a twist of lemon peel, of course. I was beginning to get the hang of Louisville.

IF YOU GO ...

WHERE TO STAY:

I opted for the new 21c Museum Hotel, 700 W. Main St. The rooms — equipped with iPods, modern art and other hip extras — have an industrial-chic look, and the lobby is home to a trendy art gallery. Doubles from $139 a night. (877) 217-6400, www.21chotel.com.

For a hotel oozing with tradition, head to the Seelbach Hilton, 500 Fourth Ave. With its posh lobby and recently restored Old Seelbach Bar, it's no surprise that Al Capone, F. Scott Fitzgerald and nine U.S. presidents have been guests here. The downtown location is central to most attractions. From about $130. (800) 445-8667, www.hilton.com.

The spacious rooms )from $69) and free breakfast make the Best Western Brownsboro Inn at 4805 Brownsboro Road a budget traveler's boon. It's almost seven miles from downtown, however, so you'll need a car. (800) 428-2627, www.bestwestern.com.

WHERE TO EAT:

Jack Fry's at 1007 Bardstown Road has superbly executed American cuisine, ranging from the succulent Jack's burger to the rich lobster campanelle. The shrimp and grits beat out all the competition in town. With a blaring piano and a fun-loving crowd, it can sometimes get loud, but that's a small downside to this otherwise classy place. Entrees average around $27. (502) 452-9244)

Locals throng to Lynn's Paradise Cafe, 984 Barret Ave., for its fun, kitschy vibe and hefty portions of mac and cheese, fried chicken and other comfort food. It's a treat for lunch and dinner, but is especially known for its hearty breakfasts, which average around $10 a person. (502) 583-3447.

Proof on Main at 702 W. Main St. has fine art on the walls and great service, but the consistently excellent menu is the real draw. The bison and bass, both raised locally, were particularly tasty. Entrees average $25. (502) 217-6360.

WHAT TO DO: