Over the years the pace of the renewal picked up dramatically, with the last abandoned houses now undergoing renovation. As many as ten cruise ships can berth in the harbor, although looking down from my hotel roof, I could hardly imagine it—four of them took up a monstrous amount of space. A revitalized restaurant scene on Calle Fortaleza, which began with the Parrot Club in 1996, has popularized Nuevo Latino cuisine and sent local chef Roberto Treviño, who cooked at both the Parrot Club and Aguaviva, to challenge Mario Batali on Iron Chef America (sadly, his catfish seviche lost). In these chic new spots, the martini usurps the piña colada, the city's claim to cocktail fame since 1963.

O nly seven streets by seven, Old San Juan is small enough to be walked end to end in twenty-five minutes, so after a few days, I began to know people. On a Friday night, in the alley Callejón de la Capilla, outside the Nuyorican Café, my husband and I run into a Midwestern couple we'd met at a hotel cocktail hour. We stand together drinking beer from plastic cups, waiting for it to get late enough for the salsa band to begin. We are too old to consider most of the other clubs, like the Milk or the Pink Skirt, which sucks in crowds of local girls in miniskirts followed by strutting guys in untucked button-down shirts.

Here in the alley, a crowd of all ages ebbs and flows. Finally, we take our seats in the cavernous Nuyorican Café, and the salsa singer, Wilfredo, in matching cream-colored vest and newsboy cap, impatiently urges his band onto the stage. His casual group is barely assembled when he signals a young woman wearing thick eyeliner, a pouf skirt, and work boots to begin shaking her beaded chekere in that familiar syncopated beat. With the salsa under way, the dance floor fills with couples who, once they find an empty spot, seem to flip a switch that sets their hips rotating, as if they were born to move this way.

Our friends do a basic cha-cha they learned in Michigan. My husband and I finally put down our Heinekens and find space in the back to dance. Nobody pays any attention as we shuffle away, putting the accent on different wrong beats, because salsa dancing is not sport but something all Puerto Ricans do at family parties. By now, the small stage has filled with nine musicians, playing elbow to elbow, the trombone nearly hitting the heads of the singers.

When the music stops, the air outside is comfortably warm and the streetlights give off a soft glow. It's well past midnight, but the streets are as busy as in the middle of the day, and despite the hour, there is no drunken sloppiness. We seek out a view of the water and the illuminated fortresses. "Take advantage of the romance here," a Florida man chides us. "If not, shame on you."

A few days later, as I rush downstairs at Da House Hotel to head for the airport, the young receptionist urges me to relax, explaining that an hour and a half is more than enough time to make a plane in San Juan. He carries my bag down two flights of stairs. (The hotel, a former monastery, has no elevator.) The street is quiet, with signs of the previous night's party in the piles of trash on the cobblestones, and no radio taxi. The young man waits with me. It takes a moment, but even without his hat I recognize him—it's Wilfredo, the singer in the salsa band. "Yeah," he says, pleased at the recognition. "That was a good night. We were jammin'."