Mantua. Another one of those Italian towns you've never heard of, right?

Well, let's start with the bedroom.

A vast, dimly lit chamber with thick walls and bare tile floor, it is hardly cozy. More than 26 feet wide and roughly that tall, it is a chilly cube that nestles deep in the recesses of the Castello di San Giorgio.

But since 1475, when its frescoed walls shone fresh, the chamber has been acclaimed as one of the world's most beautiful rooms. Even now its imposing portraits of the Gonzaga family, with their elegant courtiers, handsome horses and sleepy dogs, stand among Italy's most famous art treasures.

While the bedroom is a cultural marvel, it's just one of Mantua's treasures.

In their heyday, the Gonzaga, who ruled this city from 1328 to 1707, competed for top talent with the Medici of Florence, kings of France and assorted popes. Art stars who decorated their palazzos and churches include Caravaggio, Correggio, Mantegna, Raphael, Rubens, Tintoretto and Titian.

Much of that art eventually found its way into museums around the world. One of the prizes, Correggio's sensual painting of a nymph being seduced by a god disguised as a teddy-bear cloud, was even lent to the Minneapolis Institute of Art a few years ago.

Having encountered Gonzaga art seemingly everywhere, last summer I decided to see firsthand what remains in the place they called home.

On the plains of Lombardy in northern Italy, Mantua rises amid lush fields of maize, rice, sunflowers and wheat at a bend of the Mincio, a tributary of the Po River. Verona lies due north, and Venice is 60 miles east.

Midday silence

I arrived by train and hopped into a taxi. From the window, I spied a market plaza, narrow streets and tile-roofed buildings that seem largely untouched by time, as in Florence, Sienna and other ancient Italian towns. Mantua prohibits cars in the old town, so I made the final approach to my hotel, the modest Hotel Broletto, on foot. There, I dropped my bag and set out to explore.

It was about 2 p.m. on a sweltering June day, so I first stopped for a gelato at a plaza around the corner.

Then I peered into the Rotonda of San Lorenzo, an unusual circular brick church dating to 1082, and checked out the Basilica of Sant'Andrea, a grandiose neoclassical building designed in 1471 by papal adviser Leon Battista Alberti.

Decorated with pale frescoes that simulate carved stone, the vast, airy interior feels as big as St. Peter's in Rome. Impressed, I was beginning to understand why Mantua had been a must-see town for the likes of Leonardo da Vinci, who likely toured the church under construction when he visited in 1499.

As I headed for the nearby Piazza Sordello, which boasts the Duomo, or cathedral, and the Ducal Palace, I was mystified by the silence. Awnings hung limp over arcades, shops were shuttered, streets were strangely quiet. Mantua seemed a ghost town.

There was not another soul in the cathedral, a complicated pastiche of 1400s Gothic brick fancied up with an 18th-century white marble facade. Distracted by the swags, columns and clutter inside, I stopped short at a side chapel dedicated to St. Agatha, a third-century Sicilian martyr about whom I knew nothing.

As depicted by Lorenzo Costa, a minor Mantuan painter, St. Agatha — arms tied behind her back — was being tortured by two burly thugs, one of whom had clamped red-hot tongs around one of her bare breasts. Yikes! Not even wincing, she rolls her eyes heavenward as if to say, "The things we gals have to put up with."

The painting is pure kitsch, but oh, so topical these days, alas. I quickly texted photos of her to friends back home.

Exhausted by the heat and my encounter with Agatha, I retreated to my hotel for a siesta.

When I emerged again in the early evening, the town was beginning to stir. Teens bicycled past as white-jacketed waiters set up al fresco tables. Then I realized, duh, that Mantua operates on a truly Mediterranean schedule. Shops are open from 9 a.m. to 12:30 p.m. and again from 3:30 to 7:30 p.m. Everyone but daft tourists shuts down for three hours in the heat of the day.

From warlords to culturati

The Gonzaga were warlords at heart, especially in the 14th to 16th centuries, when the Italian peninsula was a cauldron of squabbling city-states. They seized power in 1328 in a bloody coup against Mantua's previous ruling family and spent the next 300 years consolidating their influence via war, dynastic marriages and art commissions.

They were on the rise in 1460, when Ludovico Gonzaga lured Andrea Mantegna from nearby Padua to be his court painter. Known for his dramatic perspectives, elegant drawing and references to ancient Rome, Mantegna introduced Renaissance culture to Mantua. Most of the work he did there is now elsewhere, in museums, but his amazing frescoes remain in that oversized bedroom, known as the Camera degli Sposi, or bridal chamber.

If Ludovico Gonzaga and his wife, Barbara, really did snuggle into bed there — and in those days rooms served many purposes — politics, family and daily life were never far off. Above the fireplace, the somber couple sit in a garden niche, surrounded by children, advisers, a bevy of handsome young men and one of the court dwarfs. A dog slumbers under a chair while Ludovico confers with a courtier, perhaps about the letter in hand.

On an adjacent wall, Ludovico greets a son who has just returned from Rome, while staff, dogs and horses await orders. Ripe fruit hangs in orchards, and walled cities climb over distant hills.

Even the heavens are on call. Above the door, adorable putti — little boys fitted with colorful butterfly wings — hold up a gilded proclamation; musicians, servants and more putti peer in through a painted opening in the ceiling, beyond which puffy clouds drift through blue skies. Finished in 1474 after nearly a decade of labor, the elegant fresco celebrates family life in an Arcadian vision of power and prosperity.

Over the centuries, the Castello di San Giorgio was absorbed into what is now known as the Ducal Palace, a 500-room fortress spanning more than 7 acres with 15 courtyards and gardens (not all of them open to the public). It's an exhausting maze. After hiking through galleries of relics, costumes, ceramics, bronzes and even napkins folded into origami birds, I escaped for fresh air and a lovely evening stroll along the water.

In the 1200s, Mantuans engineered a stretch of the Mincio into four lakes to prevent flooding and serve as a defensive barricade. Three of the lakes survive and partly surround the city's core, separating the old town from the modern, industrial suburbs whose rusty smokestacks rise across the water.

Pleasure palace

After an early breakfast the next day, I headed for the Palazzo Te, a legendary pleasure palace about a 20-minute walk from the old town past quiet neighborhood bars and buildings with shutters on the windows. Another Gonzaga — Federico II — had this beauty built between 1526 and 1535 as a love nest for his mistress Isabella Boschetti. Mantua was then at the height of its power, and Federico wanted nothing but the best.

Naturally he turned to Rome, where Michelangelo had signed off on his revolutionary Sistine Chapel ceiling in 1512, and the other papal favorite, Raphael, had recently died. With Raphael's death, his most successful collaborator, Giulio Romano, was available, and Federico made him an irresistible offer. As prefect of the building works, Giulio was charged with transforming Mantua from a muddy outpost into an urbane capital.

A consummate designer/manager, Giulio assembled in Mantua a vast workshop that produced everything from paintings, sculpture, tapestry and theater sets to paving, waterworks, fortifications and a fish market, which still stands. While he designed pretty much everything, the art, objects and construction were mostly executed by staff.

The Palazzo Te is Giulio's most famous project, a sprawling complex of salons, gardens, grottoes and moats in a leafy park that had been the Gonzagas' stud farm. The first salon, in fact, is ringed with life-size portraits of Federico's favorite thoroughbreds.

But the best known rooms are the Sala di Psiche (Psyche's Room) and the Sala dei Gigante (Hall of the Giants). The first is a lavishly frescoed dining room on whose walls and ceiling gods and mortals eat, drink, flirt, bathe and cavort with lascivious abandon.

The second is a bizarre chamber covered with a frescoed disaster scene in which giants with bulging muscles and comic-book faces are crushed by collapsing mountains, temples, columns and boulders as Zeus hurls thunderbolts at them from Mount Olympus.

Such extravagance, of course, cost a bundle. Eventually the Gonzagas' cultural aspirations overshot their income, and looming debts forced them to sell some 370 of their best paintings and sculpture to England's King Charles 1 in 1628.

The sale barely nicked the Gonzagas' 20,000-piece hoard of books, clocks, tapestries, gems, antiquities and other bijoux, but it did feed revolutionary fervor in England. Twenty-one years later, Charles was beheaded and his collection, too, was auctioned off.

Mantua also suffered. In 1629, the year after the sale, the city was attacked and looted by rival powers. The Gonzagas' remaining riches were plundered, tapestries cut up for saddle blankets and rare books sold for pennies in the plaza.

Weeks later, back home in Minnesota, I found myself musing about Mantua and its hot, still streets, brooding fortresses, dark churches, empty gardens and shadowy arcades. It seems a place haunted by its past, the noble arrogance of the Gonzagas frozen in courtly hauteur on the high walls of their empty palace.

From 500 years back they still rule, so much more alive in my mind than any of us shadows slipping through Mantua's slumberous heat.

Mary Abbe is a former Star Tribune arts reporter.