Few Caribbean cities are as steeped in Spanish tradition as Puerto Rico's Old San Juan. Originally built as a fortress, the old city's myriad attractions include restored 16th-century buildings and 200-year-old houses with balconies of filigreed wrought iron that overlook narrow cobblestone streets.

Spanish traditions are also apparent in the countryside -- from the festivals celebrated in honor of small-town patron saints to the paradores, inexpensive but accommodating inns whose concept originated in Spain.

Puerto Rico, 110 miles (177 km) long and 35 miles (56 km) wide, was populated by several tribes of Indians (primarily the Taíno) when Columbus landed during his second voyage in 1493. In 1508 Juan Ponce de León, the frustrated seeker of the Fountain of Youth, established a settlement on the island and became its first governor; in 1521 he founded what would become known as Old San Juan.

For three centuries the French, Dutch, and English tried unsuccessfully to wrest the island from Spain. In 1897 Spain granted the island dominion status and a year later -- as a result of the Spanish-American War -- Spain ceded it to the United States. In 1917 Puerto Ricans became U.S. citizens, and in 1952 Puerto Rico became a semiautonomous commonwealth.

Music is a special source of Puerto Rican pride, and the brash Latin sound is best characterized by the musicand dance form known as salsa, which shares not only its name with the Spanish word for "sauce" but also a zesty, hot flavor. This fusion of West African percussion, jazz (especially swing and big band) and other Latin beats (mambo, merengue, flamenco, cha-cha, rumba) is sexy and primal. Dancing to it is a chance to let go of inhibitions.

Moving to the beat of salsa isn't your only nightlife option here. In San Juan's sophisticated Condado and Isla Verde areas you'll find flashy cabaret shows and casinos. By day you can step into the Old World -- in Old San Juan, in a quiet colonial town, or on a coffee plantation. If you're the athletic type, you'll appreciate the island's many acres of golf courses, its abundant tennis courts, and its hundreds of beaches, which offer every imaginable water sport. In the extraordinary 28,000-acre Caribbean National Forest (known as El Yunque) you'll find 100-ft-high trees and dramatic mountain ranges.

If all this isn't enough, you can head to the outlying islets of Culebra, Vieques, and Mona, where the snorkeling and scuba diving are fine.