Earth : South America
The world's biggest rainforest and the largest river (Amazon), the highest mountain range outside Asia (the Andes), remote islands (Galapagos Islands, Easter Island and Fernando de Noronha), heavenly beaches (such as in Brazil's Northeastern region), wide deserts (Atacama), icy landscapes (Patagonia & Tierra del Fuego), the world's tallest waterfall (the 979m Angel Falls, in Venezuela) and one of the largest (Iguaçu Falls, Argentina and Brazil), as well as several other breathtaking natural attractions.
Besides, the work of man has also left rare gems on the continent: ruins of ancient civilizations (Machu Picchu and other Inca cities; the Moais in Easter Island) share the continent with world-class metropolises (São Paulo, Buenos Aires, Bogotá, Caracas, Santiago, Lima and Rio de Janeiro), outstanding modern architecture (Brasilia), European architecture (Buenos Aires), the oldest rock paintings in the Americas (at the Serra da Capivara), strong African heritage (in Salvador, Rio and Montevideo), genuine indigenous (Belém, Manaus, Cuzco, Lima, La Paz), charming cities built in the Andes (Caracas, Medellín, Quito, Santiago de Chile) and Eastern culture (São Paulo's enormous Japanese community), mingled with the fingerprints of Iberian colonizers. Ushuaia, the world's southernmost city and some of its biggest festivities, such as Rio's Carnival and Belem's Cirio de Nazaré, the Tango World Championship, and the Vendimia festival in Argentina, are also part of this incredibly diverse and attractive continent.
Countries and territories
Getting to South America has become much easier in recent years due to massive increases in flights to the continent by major global airlines. Although some particular places are still quite hard to reach (i.e. Paraguay, Suriname, northern Brazil), the places that you most likely want to go, such as Buenos Aires and Rio de Janeiro, are more accessible than ever before.
Beware there are no roads connecting Panama with Colombia, hence it is not possible to drive from Central America. People overcome this problem shipping their cars from Colon for easier transportation (Atlantic side in Panama) to Cartagena or Barranquilla (Colombia), or from Panama City (Pacific side of the Panama canal) to Buenaventura (Colombia) or Guayaquil(Ecuador).
The Pan-American Highway is a series of routes starting in Central America and running to the tip of South America (save for the Darien Gap between Panama and Colombia). It's an interesting option for those with a good vehicle, plenty of spare parts, and a desire to explore the western edge of the continent.
There are no rail connections between Panama and Colombia.
The Union of South American Nations gives visa-free access and a customs union between all countries in South America.
International flights are generally expensive within South America and from South America to other parts of the world. Within each country the national domestic flights can be more reasonable. Therefore, it may be more economical (cost wise) to fly to the border city of one country, cross the border by ground transportation and fly onwards from the other side of the border. For example, for one to go from Lima to Santiago, the traveller might fly from Lima to Tacna, take a bus or taxi to Arica, and fly onwards from Arica to Santiago.
There are no cross-country train services in South America, and with the exception of Argentina and Chile, domestic networks are quite limited, such as a railway in Bolivia, from Oruro to Villazón, passing through Uyuni, Tupiza and some other places, and a railway in Brazil, linking regional capitals Belo Horizonte and Vitória. There are a number of very scenic "tourist trains" though, including the 445km Quito-Guayaquil route in Ecuador.
Buses are the main form of land transport for much of the continent... for longer distances you're often better off flying but if you like you can use the bus but it may be a longer drive.
Spanish is the official language in all countries except Brazil, Guyana, Suriname and French Guiana, and is widely spoken even in the countries that are not historically Spanish speaking. Portuguese is the official language in Brazil, which comprises about half the population and land area of the continent. There are also many indigenous peoples living in South America who speak their own languages, and if you are really going off the beaten track, you might have to familiarize with them too. In Guyana, Suriname and French Guiana, the official languages are English, Dutch and French respectively.
South America has some of the most incredible sights in the world but is a large continent and getting around it can be slow and difficult. The most popular things to see include the ancient ruins of Machu Picchu high up the Peruvian Andes. In terms of natural beauty it's hard to beat the stunning Iguazu Falls that span that three countries (Brazil, Argentina and Paraguay) and the unique Mount Roraima in the frontier between Venezuela, Guyana and Brazil. Delightful remnants of Spanish colonialism can be found in many countries but is perhaps best in Cartagena, Colombia. Meanwhile exciting vibrant cities like Buenos Aires and Rio de Janeiro provide the best taste of urban life in 21st Century South America.
South America is a magnificently varied part of the world and tremendously hospitable, South America offers many different alternative travel experiences and destinations. Most any adventurous activity can be enjoyed here in stunning and unique places. Rafting, trekking, jungle hikes, biking, zip lining, bungy jumping, diving, surfing, mountain climbing, para sailing, kite surfing, bird watching, discovering the huge variety of flora and fauna in the jungles and mountains, boating down the Amazon River. Amazing Peru & Beyond  is a operator in South America such a Classic Inca Trail, Galapagos, etc..
Wearing or carrying items which may identify you as an affluent tourist can be a mistake. You shouldn't pack anything that you would be upset to lose. Leave expensive jewelry, watches and other items of value at home and only carry what you need. That goes for credit cards and other documents as well; if you have no need for them leave them behind in the hotel safe, only take what money you are likely to spend with you.
Tap water in many countries is not drinkable, it's wise to purify your own or buy bottled water. Malaria and Yellow fever can be a risk as well on the continent, check with a travel clinic or your doctor before heading out to see if you'll be in a high-risk area.