Argentina, Uruguay, Brazil

Glamorous and gritty, Buenos Aires is two cities in one. What makes Argentina's capital so fascinating is its dual heritage—part European, part Latin American. Plaza de Mayo resembles a grand square in Madrid, and the ornate Teatro Colón would not be out of place in Vienna. But you’ll know you’re in South America by the leather shoes for sale on cobbled streets and impromptu parades of triumphant soccer fans. Limited-production wines, juicy steaks, and ice cream in countless flavors are among the old-world imports the city has perfected.

Uruguay’s capital city hugs the eastern bank of the Río de la Plata. A massive coastal promenade (malecón) that passes fine beaches, restaurants, and numerous parks recalls the sunny sophistications of the Mediterranean and is always dotted with Montevideans strolling, exercising, and lounging along the water. Montevideo has its share of glitzy shopping avenues and modern office buildings, balanced with its historic old city and sumptuous colonial architecture, as well as numerous leafy plazas and parks. It is hard not to draw comparisons to its sister city Buenos Aires across the river, and indeed Montevideo strikes many as a calmer, more manageable incarnation of Argentina's capital.When the weather's good, La Rambla, a 22-km (14-mile) waterfront avenue that links the Old City with the eastern suburbs and changes names about a dozen times, gets packed with fishermen, ice-cream vendors, and joggers. Around sunset, volleyball and soccer games wind down as couples begin to appear for evening strolls. Polls consistently rate Montevideo as having the highest quality of life of any city in Latin America. After one visit here, especially on a lovely summer evening, you probably will agree.

Welcome to the Cidade Maravilhosa, or the Marvelous City, as Rio is known in Brazil. Synonymous with the girl from Ipanema, the dramatic views from Christ the Redeemer atop Corcovado mountain, and fabulously flamboyant Carnival celebrations, Rio is a city of stunning architecture, abundant museums, and marvelous food. Rio is also home to 23 beaches, an almost continuous 73-km (45-mile) ribbon of sand.As you leave the airport and head to Rio's beautiful Zona Sul (the touristic South Zone), you'll drive for about 40 minutes on a highway from where you'll begin to get a sense of the dramatic contrast between beautiful landscape and devastating poverty. In this teeming metropolis of 12 million people (6.2 million of whom live in Rio proper), the very rich and the very poor live in uneasy proximity. You'll drive past seemingly endless cinder-block favela, but by the time you reach Copacabana's breezy, sunny Avenida Atlântica—flanked on one side by white beach and azure sea and on the other by condominiums and hotels—your heart will leap with expectation as you begin to recognize the postcard-famous sights. Now you're truly in Rio, where cariocas (Rio residents) and tourists live life to its fullest.Enthusiasm is contagious in Rio. Prepare to have your senses engaged and your inhibitions untied. Rio seduces with a host of images: the joyous bustle of vendors at Sunday's Feira Hippie (Hippie Fair); the tipsy babble at sidewalk cafés as patrons sip their last glass of icy beer under the stars; the blanket of lights beneath the Pão de Açúcar (Sugarloaf Mountain); the bikers, joggers, strollers, and power walkers who parade along the beach each morning. Borrow the carioca spirit for your stay; you may find yourself reluctant to give it back.

Glamorous and gritty, Buenos Aires is two cities in one. What makes Argentina's capital so fascinating is its dual heritage—part European, part Latin American. Plaza de Mayo resembles a grand square in Madrid, and the ornate Teatro Colón would not be out of place in Vienna. But you’ll know you’re in South America by the leather shoes for sale on cobbled streets and impromptu parades of triumphant soccer fans. Limited-production wines, juicy steaks, and ice cream in countless flavors are among the old-world imports the city has perfected.