Argentina in the context of "Rock strata"

Bolivia, officially the Plurinational State of Bolivia, is a landlocked country located in central South America. The country features diverse geography, including vast Amazonian plains, tropical lowlands, mountains, the Gran Chaco, warm valleys, high-altitude Andean plateaus, and snow-capped peaks, encompassing a wide range of climates and biomes across its regions and cities. It includes part of the Pantanal, the largest tropical wetland in the world, along its eastern border. It is bordered by Brazil to the north and east, Paraguay to the southeast, Argentina to the south, Chile to the southwest, and Peru to the west. The seat of government is La Paz, which contains the executive, legislative, and electoral branches of government, while the constitutional capital is Sucre, the seat of the judiciary. The largest city and principal industrial center is Santa Cruz de la Sierra, located on the Llanos Orientales (eastern tropical lowlands), a mostly flat region in the east of the country with a diverse non-Andean culture.

The sovereign state of Bolivia is a constitutionally unitary state divided into nine departments. Its geography varies as the elevation fluctuates, from the western snow-capped peaks of the Andes to the eastern lowlands, situated within the Amazon basin. One-third of the country is within the Andean mountain range. With an area of 1,098,581 km (424,164 sq mi), Bolivia is the fifth-largest country in South America after Brazil, Argentina, Peru and Colombia, and, alongside Paraguay, is one of two landlocked countries in the Americas. It is the largest landlocked country in the Southern Hemisphere. Bolivia had a population of 11.4 million as of the latest census in 2024. It is multiethnic, including Amerindians, Mestizos, and the descendants of Europeans and Africans. Spanish is the official and predominant language, although 36 indigenous languages also have official status, of which the most commonly spoken are Guaraní, Aymara, and Quechua.

Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, extending along a narrow strip of land between the Andes Mountains and the Pacific Ocean. According to the 2024 census, Chile had an enumerated population of 18.5 million. The country covers a territorial area of 756,102 square kilometers (291,933 sq mi), sharing borders with Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage to the south. It also administers several Pacific islands, including Juan Fernández, Isla Salas y Gómez, Desventuradas, and Easter Island, and claims about 1,250,000 square kilometers (480,000 sq mi) of Antarctica as the Chilean Antarctic Territory. The capital and largest city is Santiago, and the national language is Spanish.

Spain conquered and colonized the region in the mid-16th century, replacing Inca rule; however, they failed to conquer the autonomous tribal Mapuche people who inhabited what is now south-central Chile. Chile emerged as a relatively stable authoritarian republic in the 1830s after their 1818 declaration of independence from Spain. During the 19th century, Chile experienced significant economic and territorial growth, putting an end to Mapuche resistance in the 1880s and gaining its current northern territory in the War of the Pacific (1879–83) by defeating Peru and Bolivia.

The Andes (/ˈændiːz/ AN-deez), Andes Mountains or Andean Mountain Range (Spanish: Cordillera de los Andes; Quechua: Anti) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is 8,900 km (5,500 mi) long and 200 to 700 km (120 to 430 mi) wide (widest between 18°S and 20°S latitude) and has an average height of about 4,000 m (13,000 ft). The Andes extend from south to north through seven South American countries: Argentina, Chile, Bolivia, Peru, Ecuador, Colombia, and Venezuela.

Along their length, the Andes are split into several ranges, separated by intermediate depressions. The Andes are the location of several high plateaus—some of which host major cities such as Arequipa, Bogotá, Cali, Medellín, El Alto, La Paz, Mérida, Santiago and Sucre. The Altiplano Plateau is the world's second highest after the Tibetan Plateau. These ranges are in turn grouped into three major divisions based on climate: the Tropical Andes, the Dry Andes, and the Wet Andes.

The Andean civilizations were South American complex societies of many indigenous people. They stretched down the spine of the Andes for 4,000 km (2,500 miles) from southern Colombia, to Ecuador and Peru, including the deserts of coastal Peru, to north Chile and northwest Argentina. Archaeologists believe that Andean civilizations first developed on the narrow coastal plain of the Pacific Ocean. The Caral or Norte Chico civilization of coastal Peru is the oldest known civilization in the Americas, dating back to 3500 BCE. Andean civilizations are one of at least five civilizations in the world deemed by scholars to be "pristine." The concept of a "pristine" civilization refers to a civilization that has developed independently of external influences and is not a derivative of other civilizations.

Despite the severe environmental challenges of high mountains and hyper-arid desert, the Andean civilizations domesticated a wide variety of crops, some of which, such as potatoes, peppers, peanuts, manioc, chocolate, and coca, became of worldwide importance. The Andean civilizations were noteworthy for monumental architecture, an extensive road system, textile weaving, and many unique characteristics of the societies they created.

The Inca Empire, officially known as the Realm of the Four Parts (Quechua: Tawantinsuyu pronounced [taˈwantiŋ ˈsuju], lit. 'land of four parts'), was the largest empire in pre-Columbian America. The administrative, political, and military center of the empire was in the city of Cusco. The Inca civilisation rose from the Peruvian highlands sometime in the early 13th century. The Portuguese explorer Aleixo Garcia was the first European to reach the Inca Empire in 1524. Later, in 1532, the Spanish began the conquest of the Inca Empire, and by 1572 the last Inca state was fully conquered.

From 1438 to 1533, the Incas incorporated a large portion of western South America, centered on the Andean Mountains, using conquest and peaceful assimilation, among other methods. At its largest, the empire joined modern-day Peru with what are now western Ecuador, western and south-central Bolivia, northwest Argentina, the southwesternmost tip of Colombia and a large portion of modern-day Chile, forming a state comparable to the historical empires of Eurasia. Its official language was Quechua.

The Río de la Plata basin (Spanish: Cuenca del Plata, Portuguese: Bacia do Prata), more often called the River Plate basin in scholarly writings, sometimes called the Platine basin or Platine region, is the 3,170,000-square-kilometre (1,220,000 sq mi) hydrographical area in South America that drains to the Río de la Plata. It includes areas of southeastern Bolivia, southern and central Brazil, the entire country of Paraguay, most of Uruguay, and northern Argentina. Making up about one fourth of the continent's surface, it is the second largest drainage basin in South America (after the Amazon basin) and one of the largest in the world.

The main rivers of the La Plata basin are the Paraná River, the Paraguay River (the Paraná's main tributary), and the Uruguay River.

The Antarctic Treaty and related agreements, collectively known as the Antarctic Treaty System (ATS), regulate international relations with respect to Antarctica, Earth's only continent without a native human population. It was the first arms control agreement established during the Cold War, designating the continent as a scientific preserve, establishing freedom of scientific investigation, and banning military activity; for the purposes of the treaty system, Antarctica is defined as all the land and ice shelves south of 60°S latitude. Since September 2004, the Antarctic Treaty Secretariat, which implements the treaty system, is headquartered in Buenos Aires, Argentina.

The main treaty was opened for signature on 1 December 1959, and officially entered into force on 23 June 1961. The original signatories were the 12 countries active in Antarctica during the International Geophysical Year (IGY) of 1957–58: Argentina, Australia, Belgium, Chile, France, Japan, New Zealand, Norway, South Africa, the Soviet Union, the United Kingdom, and the United States. These countries had established over 55 Antarctic research stations for the IGY, and the subsequent promulgation of the treaty was seen as a diplomatic expression of the operational and scientific cooperation that had been achieved. As of 2024, the treaty has 58 parties.

A megacity is a very large city, typically with a population of more than 10 million people. The United Nations Department of Economic and Social Affairs (UN DESA) in its "World Urbanization Prospects" report defines megacities as urban agglomerations with over 10 million inhabitants. A University of Bonn report holds that they are "usually defined as metropolitan areas with a total population of 10 million or more people". Elsewhere in other sources, from five to eight million is considered the minimum threshold, along with a population density of at least 2,000 per square kilometre. The terms conurbation, metropolis, and metroplex are also applied to the latter.

The total number of megacities in the world varies between different sources and their publication dates. The world had 32 according to EU Global Human Settlement Layer (in 2024), 33 according to UN DESA (in 2025), 39 according to the OECD, 42 according to Demographia (in 2025), and 45 according to CityPopulation.de (in 2023). The later two add 13 additional cities that are calculated outside the range otherwise. In total, at most 53 unique places are mentioned as megacities across these sources, although some of these are just agglomerated differently between them. A good percentage of these urban agglomerations are in China and India. The other three-to-five countries with more than one megacity are Brazil, Indonesia, Japan, Pakistan, and the United States. African megacities are present in Angola, Democratic Republic of the Congo, Egypt, Nigeria and South Africa; European megacities are present in France, Germany, Russia, the United Kingdom, and Turkey (also in Asia); megacities can be found in Latin America in the countries of Brazil, Mexico, Colombia, Peru, and Argentina.

São Paulo (/ˌsaʊ ˈpaʊloʊ/, Portuguese: [sɐ̃w ˈpawlu] ) is one of the 26 states of the Federative Republic of Brazil and is named after Saint Paul of Tarsus. It is located in the Southeast Region and is bordered by the states of Minas Gerais to the north and northeast, Paraná to the south, Rio de Janeiro to the east and Mato Grosso do Sul to the west, in addition to the Atlantic Ocean to the southeast. It is divided into 645 municipalities. The total area is 248,219.481 square kilometres (95,838.077 square miles) km, which is equivalent to 2.9% of Brazil's surface, being slightly larger than the United Kingdom. Its capital is the municipality of São Paulo.

With more than 44 million inhabitants in 2022, São Paulo is the most populous Brazilian state (around 22% of the Brazilian population), the world's 28th-most-populous sub-national entity and the most populous sub-national entity in the Americas, and the fourth-most-populous political entity of South America, surpassed only by the rest of the Brazilian federation, Colombia, and Argentina. The local population is one of the most diverse in the country and descended mostly from Italians, who began immigrating to the country in the late 19th century; the Portuguese, who colonized Brazil and installed the first European settlements in the region; Indigenous peoples, many distinct ethnic groups; Africans, who were brought from Africa as enslaved people in the colonial era and migrants from other regions of the country. In addition, Arabs, Armenians, Chinese, Germans, Greeks, Japanese, Spanish and American Southerners also are present in the ethnic composition of the local population.

Venetian, also known as wider Venetian or Venetan (łengua vèneta [ˈɰeŋɡwa ˈvɛneta] or vèneto [ˈvɛneto]), is a Romance language spoken natively in the northeast of Italy, mostly in Veneto, where most of the five million inhabitants can understand it. It is sometimes spoken and often well understood outside Veneto: in Trentino, Friuli, the Julian March, Istria, and some towns of Slovenia, Dalmatia (Croatia) and the Bay of Kotor (Montenegro) by a surviving indigenous Venetian population, and in Argentina, Australia, Brazil, Canada, Mexico, the United States and the United Kingdom by Venetians in the diaspora.

Although referred to as an "Italian dialect" (Venetian: diałeto; Italian: dialetto) even by some of its speakers, the label is primarily political, referring to geography and not linguistics. In the realm of linguistics, Venetian is often considered a separate language from Italian, with its own local varieties. Its precise place within the Romance language family remains somewhat controversial however. Both Ethnologue and Glottolog group it into the Gallo-Italic branch (and thus, closer to French and Emilian–Romagnol than to Italian). Devoto, Avolio and Ursini reject such classification, and Tagliavini [it] places it in the Italo-Dalmatian branch of Romance.