As a friend planned her upcoming Portuguese vacation, I quietly encouraged (OK, tirelessly browbeat) her into taking a side trip from Lisbon to Porto. "I'd only have time to get off at the train station, turn around, and come back," she protested.

"That's reason enough to go," I told her.

I wasn't being facetious. Porto's São Bento Train Station qualifies as one of the world's great unrecognized artistic treasures, a transportation hub cum ethereal landmark. Hanging in its long cathedral-worthy vestibule are no fewer than 20,000 painted tiles offering a sweeping tour of Portugal's history, landscape and culture by way of monumental panels. It's the cultural scenes that are most evocative: a line of men threshing their way through a ripe field; knots of women floating down a river on elegantly carved wooden boats; a girl standing in a village square, looking out at the viewer, her hair bundled up in a scarf and a downy calf leaning against her legs.

Gleaming in blue and white, painted in the early 20th century by master tile painter Jorge Colaço, the images have a haunting, elegiac beauty, as bittersweet as fado music, Portugal's lovelorn folk ballad.

The images are witnesses, in a way -- traces of a gorgeous world half lost and half salvaged.

They are also fitting emblems of Porto's limitless talent to surprise, and the city's dedication to salvaging the best of its own back streets.

Lisbon, of course, wears the permanent crown as Portugal's cultural beauty queen, and Porto slipped into the thankless role as the country's ugly stepsister of a second city for a reason. Rich in the 17th and 18th centuries -- when it was a trading center famous for its Douro River Valley Port wine -- the northern Portuguese city slowly devolved into a largely industrial, gritty eyesore. By the 20th century, big chunks of its medieval historic core had been left to rot into slumped slums.

Then Porto's fortunes doubled back. First came the UNESCO designation of the city's medieval center as a World Cultural Heritage Site in 1996. Then Porto won the title of European Capital of Culture in 2001. The twin salute triggered a recognition of what had been lost -- and a concerted effort to reclaim things. Slowly restaurants, cafes, bars and shops moved back into the city center and then larger landmark projects got launched, building to a frenzy of exuberant activity in the past five years.

Posh spot in the city center

When I made a weeklong visit last October, Porto's revival was dramatically apparent, and not just at my hotel.

When the InterContinental Hotel brand took over the 18th-century mansion Porto Palacio das Cardosas, preserving the landmark's baroque façade, it punctuated the city center's rise. With a flourish. The sprawling cleaned-up villa is now all swish grandeur, outdoing even Lisbon's poshest hangouts. The complex encompasses a wellness center, formal greenhouse restaurant, cafe Astoria (the better culinary choice), and suitably neo-baroque guestrooms, each a swirl of damask, silver-leafed desks, padded leather headboards, marble bathrooms and jewel-toned wing chairs.

In the end, of course, we don't travel for a glossy hotel room. What really turns a place into something transporting is both more vague and more visceral: Maybe it's the quality of light, or a briny tropical perfume or a singular kind of dreamy beauty.

I didn't find any of that on my first day, joining one of the crammed riverboat rides down the Douro. The city rose in graceful tiers above the water but mostly I felt distanced from the blur of scenery floating by. Instead, the moment I was truly transported was the moment I hit the ground and started to aimlessly wander.

Just behind the hotel lies the intoxicating village of Ribeira, Porto's deepest medieval core. It is a warren of cobbled back streets, with crumbling Baroque townhouses that bulge out at the front like a sea swell, Gothic churches, wrought iron balconies dangling ivy, steep climbs and dead-end alleys. The whole maze wraps in on itself, like a storied secret or a Portuguese casbah, not sinister but contained. It reveals itself slowly.

A rich culinary scene

The neighborhood is also the epicenter of Porto's culinary revival, which is reason enough to head north from Lisbon. In fact, the best food I sampled in Portugal got dished up at two restaurants that stare at each other cautiously across a hilly street in the historic core.

One comes seriously pedigreed. This is DOP, where top chef Rui Paula plates updated Portuguese cuisine in a sleek dining room punctuated by high windows, gray banquettes, and gleaming dark wood floors. The drama, though, is all on the plates, from an octopus carpaccio dotted with pomegranate seeds to chunks of lobster roused by subtle, tart orange sauce. Even better: a traditional rustic rice dish gone upscale with veal, pork, prawns and calamari, and a suckling pig wrapped up in crackling lacquered skin.

The restaurant I'd go back to was the more casual Traça. A three-level white stucco warren hung with cow skulls, Traça seems to spill out onto the cobblestones; it's a continuous fiesta of communal tables, laughter, porto guzzling and the kind of elevated, only-in-Portugal food that isn't afraid to be traditional. That means stewed squid in its own ink or a supernal heap of blood sausage tossed with eggs, potatoes and red peppers in a black skillet. To finish: the airiest cheese mousse topped with red berries and crunch of crumbled biscuit.

Porto's must-see sights

If Ribeira's finds must be ferreted out, Porto counters with some don't-miss attractions that make its name as a cultural center. If you can drag yourself away from wandering the back streets, consider the touristic trifecta.

The first obligatory stop is Sé Cathedral, a monument that changed shape along with the city. Originally a 12th-century Romanesque showpiece, it added Gothic cloisters and Baroque chapels. You don't have to be an architectural historian, though, to appreciate the morphing church. One shimmering all-silver altarpiece, exploding with metallic light, was enough spectacle for me.

The other two cultural spectacles are more contemporary. First, peek into the Casa da Música, a concert hall designed by Dutch star architect Rem Koolhaas and opened in 2005, underscoring the city's arty ascendance. If you don't have time to attend one of the almost nightly concerts, then take the afternoon tour, which includes a stop at the Orange Room, where the floor emits bird songs and percussion beats when you stop on it.

Then grab a cab to the suburban Serralves Museum of Contemporary Art, a white cubist building surrounded by expansive gardens that proves Porto can get downright postmodern when it wants. When I stopped in, the focus was on interactive pieces, including a log seesaw that people could ride, and a room lined with tinfoil that visitors could scrawl all over. What they scrawled (mostly initials, and the promise "I Will Not Make Boring Art") makes a winning case against interactive art, but the gallery compensated with an exhibit of Robert Morris' video art.

To me, the shelves of artisanal crafts on sale at A Vida Portuguesa, back downtown, looked more artful and exuded an actual sense of place. As much curated gallery as boutique, A Vida showcases majolica ceramics, straw baskets, Portuguese soaps and candles. I was torn between a wool horse blanket, woven in the mountains, that came banded with vivid stripes of blue, yellow, green and orange, and a handkerchief embroidered with candy-colored hearts, floral garlands and love poems. "Country girls in northern Portugal would make these and give them to the boys they loved," the sales clerk told me. "If the boy wore it around his neck it was like an engagement ring; if he handed it back to the girl, it meant there was no hope."

That made the choice easy. I didn't need another valentine from Porto; the city was valentine enough. So I settled for the bigger souvenir. Only in Porto would a horse blanket be elevated to high art, and all those swirling colors seemed to echo the town's own exuberance, now finally fully revealed.

Raphael Kadushin writes for Conde Nast Traveler, National Geographic Traveler and other publications. He lives in Madison, Wis.