• Manzana de las Luces, Buenos Aires, Argentina: The Manzana de las Luces (Block of Lights) served as the intellectual center of the city in the 17th and 18th centuries. This land was granted in 1616 to the Jesuits, who built San Ignacio -- the city's oldest church -- still standing at the corner of Bolívar and Aslina streets. It's worth a visit to see the beautiful altar.

  • Teatro Colón, Buenos Aires, Argentina: The majestic Teatro Colón, completed in 1908, combines a variety of European styles, from the Ionic and Corinthian capitals and French stained-glass pieces in the main entrance to the Italian marble staircase and exquisite French furniture, chandeliers, and vases in the Golden Hall. The Colón has hosted the world's most important opera singers.

  • Tiwanaku, Bolivia: The Tiwanaku lived in Bolivia from 1600 B.C. to A.D. 1200. Visit the Tiwanaku archaeological site, which is about 2 hours from La Paz, and you'll see proof of some of the amazing feats of this pre-Columbian culture. The stone-carved Sun Gate could gauge the position of the sun. The technologically advanced irrigation system transformed this barren terrain into viable farmland. The enormous and intricately designed stone-carved monoliths found here give testament to the amazing artistic talents of these people. Much here still remains a mystery, but when you walk around the site, it's exciting to imagine what life must have been like here for the Tiwanaku.

  • Potosí, Bolivia: Once one of the richest cities in the world and now one of the poorest, Potosí is a fascinating but tragic place. A silver mining town that once bankrolled the Spanish empire, Potosí is a high-altitude relic featuring beautiful church architecture and primitive mining, both of which you can experience firsthand.

  • Brasília, Brazil: Built from scratch in a matter of years on the red soil of the dry cerrado, Brasília is an oasis of modernism in Brazil's interior. Marvel at the clean lines and functional forms and admire some of the best modern architecture in the world.

  • Pelourinho, Brazil: The restored historical center of Salvador is a treasure trove of baroque churches, colorful colonial architecture, steep cobblestone streets, and large squares.

  • San Pedro de Atacama, Chiu Chiu, and Caspana, Chile: The driest desert in the world has one perk: Everything deteriorates very, very slowly. This is good news for travelers in search of the architectural roots of Chile, where villages such as San Pedro, Chiu Chiu, and Caspana boast equally impressive examples of 17th-century colonial adobe buildings and the sun-baked ruins of the Atacama Indian culture; some sites date from 800 B.C. Highlights undoubtedly are the enchanting, crumbling San Francisco Church of Chiu Chiu and the labyrinthine streets of the indigenous fort Pukará de Lasana.

  • Cartagena, Colombia: Declared a UNESCO World Heritage Site in 1984, the old walled city of Cartagena is the greatest living outdoor museum dedicated to Spanish colonial history. A walk through one of Cartagena's narrow cobblestone streets, complete with centuries-old Spanish mansions, flower-strewn balconies, and horse-drawn carriages showing tourists around town, might make you feel as if you've stepped onto the set of a colonial-era telenovela. Best of all, the finest attractions -- the plazas, the fortress, and most of the churches -- are free.

  • Quito's Old Town, Ecuador: When you walk around old Quito, you will feel as if you have stepped back in time. The oldest church here dates from 1535, and it's still magnificent. La Compañia de Jesús only dates from 1765, but it is one of the most impressive baroque structures in all of South America. It's rare to find a city with so many charming colonial-style buildings. When you wander through the streets, it really seems as if you are walking through an outdoor museum.

  • The Nazca Lines, Peru: One of South America's great enigmas are the ancient, baffling lines etched into the desert sands along Peru's southern coast. There are trapezoids and triangles, identifiable shapes of animal and plant figures, and more than 10,000 lines that can only really be seen from the air. Variously thought to be signs from the gods, agricultural and astronomical calendars, or even extraterrestrial airstrips, the Nazca Lines were constructed between 300 B.C. and A.D. 700.

  • Cusco, Peru: Cusco, the ancient Inca capital, is a living museum of Peruvian history, with Spanish colonial churches and mansions sitting atop perfectly constructed Inca walls of exquisitely carved granite blocks that fit together without mortar. In the hills above the city lie more terrific examples of Inca masonry: the zigzagged defensive walls of Sacsayhuamán and the smaller ruins of Q'enko, Puca Pucara, and Tambomachay.

  • Iglesia de San Francisco, Caracas, Venezuela: This is the church where Simón Bolívar was proclaimed El Libertador in 1813, and the site of his massive funeral in 1842 -- the year his remains were brought back from Colombia some 12 years after his death. Begun in 1575, the church shows the architectural influences of various periods and styles, but retains much of its colonial-era charm.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.