Argentina shares the majority of its western boundary with Chile, a border that runs 5,308 kilometers along the Andes Mountains from the Atacama region in the north to Tierra del Fuego in the south. The two countries share access to natural features including the Southern Patagonian Ice Field and the Beagle Channel. Bariloche and the Argentine Lake District lie directly east of Chilean destinations such as Puerto Varas and Puerto Montt, connected by the Andean lake crossing route that operates seasonally via Lago Todos los Santos. Mendoza sits 200 kilometers east of Santiago de Chile across the Cristo Redentor Pass, which closes during winter snow from June through September. The Andes crossing between these two cities follows National Route 7 in Argentina and reaches 3,832 meters elevation at the tunnel. Ushuaia serves as the departure point for Antarctic cruises that also originate from Punta Arenas in Chile, located 600 kilometers northwest across the Strait of Magellan. The northern Argentine provinces of Jujuy and Salta share highland geography with Chilean Atacama, where the Puna de Atacama plateau extends across both nations at elevations above 3,500 meters.
Bolivia borders Argentina along a 942-kilometer frontier in the northwest, where the provinces of Jujuy and Salta meet the Bolivian departments of Tarija, Potosí, and Oruro. The Quebrada de Humahuaca in Jujuy extends northward into Bolivian territory, with similar geological formations continuing into the Altiplano. Travelers moving between La Quiaca in Jujuy province and Villazón in Bolivia cross at 3,442 meters elevation, the primary border crossing for road traffic. The salt flats of Salinas Grandes in Jujuy lie 250 kilometers south of Bolivia's Salar de Uyuni, both forming part of the same high-altitude salt flat system that extends across the Andean plateau. The town of Yacuiba in Bolivia connects directly to Salvador Mazza in Salta province, a crossing used primarily for commercial traffic between the two countries. Tarija, Bolivia sits 80 kilometers north of the Argentine border, sharing wine-producing valleys with Salta province at similar elevations between 1,600 and 2,500 meters.
Paraguay shares 1,699 kilometers of border with Argentina along the Paraná and Paraguay rivers in the northeast. The Paraguayan city of Encarnación connects to Posadas in Misiones province via the San Roque González de Santa Cruz Bridge, which opened in 1990 and spans 2,550 meters. The Jesuit mission ruins of Trinidad and Jesús in Paraguay lie 30 kilometers from San Ignacio Miní in Argentina, both designated UNESCO World Heritage Sites representing the 17th and 18th century Jesuit reducciones. Asunción, the Paraguayan capital, sits 300 kilometers north of Corrientes city, accessible via National Route 12 along the Paraná River. The Triple Frontier where Argentina, Brazil, and Paraguay meet occurs at the confluence of the Iguazú and Paraná rivers, with Puerto Iguazú in Argentina, Foz do Iguaçu in Brazil, and Ciudad del Este in Paraguay forming a continuous urban area. The Argentine provinces of Formosa and Chaco share low-lying wetland geography with the Paraguayan Chaco, where the Pilcomayo River forms much of the international boundary.
Brazil shares Argentina's longest border at 1,263 kilometers, primarily along Misiones province and the eastern edge of Corrientes. The Brazilian city of Foz do Iguaçu sits adjacent to Puerto Iguazú, with Iguazú Falls physically divided between Iguazú National Park in Argentina and Iguaçu National Park in Brazil since both parks were established in the 1930s. Approximately eighty percent of the falls' individual cascades lie on the Argentine side, while the Brazilian side provides frontal panoramic views across the Iguazú River. The Tancredo Neves Bridge connects Puerto Iguazú to Foz do Iguaçu, spanning 489 meters across the Iguazú River since its completion in 1985. Santo Tomé in Corrientes province connects to São Borja in Rio Grande do Sul via the International Integration Bridge, providing access between the Argentine littoral and southern Brazil. Uruguaiana in Brazil and Paso de los Libres in Corrientes connect via the International Bridge that opened in 1947, carrying National Route 14 traffic across the Uruguay River. The Brazilian state of Rio Grande do Sul shares gaucho culture and cattle ranching traditions with Argentine provinces of Entre Ríos and Corrientes, including mate consumption and similar rural economies based on livestock.
Uruguay borders Argentina along the Río de la Plata estuary and Uruguay River, creating a 580-kilometer frontier primarily in water. Buenos Aires sits 200 kilometers west of Montevideo across the Río de la Plata, connected by ferry services that operate multiple times daily with crossing times of two to three hours. Colonia del Sacramento in Uruguay lies 50 kilometers from Buenos Aires, accessible by high-speed ferry in one hour, and preserves a Portuguese colonial quarter designated a UNESCO World Heritage Site in 1995. The Argentine city of Concordia in Entre Ríos connects to Salto, Uruguay via the Salto Grande Dam and International Bridge, completed in 1982 and spanning 3,181 meters. Fray Bentos in Uruguay sits across the Uruguay River from Gualeguaychú in Entre Ríos province, connected by the Libertador General San Martín Bridge that opened in 1976. The coastal geography of Punta del Este in Uruguay resembles that of Mar del Plata in Argentina, both serving as Atlantic beach resort cities established in the late 19th century by European immigrant populations. Carmelo in Uruguay lies near the confluence of the Uruguay River and Río de la Plata, directly across from the Argentine city of Tigre where the Paraná Delta begins.
The Falkland Islands, called Islas Malvinas in Argentina, lie 480 kilometers east of the Argentine coast in the South Atlantic. Argentina has maintained a sovereignty claim over the islands since 1833 when British forces established permanent occupation, a claim that led to the 1982 Falklands War between April 2 and June 14 of that year. Stanley, the capital of the Falkland Islands, sits at 51.6938 degrees south latitude, comparable to the latitude of Río Gallegos in Santa Cruz province. The islands support a population of approximately 3,500 residents according to the 2021 census, primarily of British descent, with an economy based on fishing licenses, wool production, and tourism. Air access to the Falklands operates from RAF Mount Pleasant, which receives weekly flights from the United Kingdom via Ascension Island, and from Punta Arenas, Chile via LAN Airlines. The British Overseas Territory covers 12,173 square kilometers across East Falkland, West Falkland, and 776 smaller islands. Wildlife tourism in the Falklands focuses on penguin colonies including king, gentoo, rockhopper, and Magellanic species, marine mammals such as sea lions and elephant seals, and seabird populations comparable to those at Península Valdés in Chubut province.
South Georgia and the South Sandwich Islands lie 1,390 kilometers east-southeast of the Falkland Islands in the South Atlantic. The United Kingdom administers these territories as part of the British Overseas Territories, while Argentina includes them in its Antarctic territorial claim as part of Tierra del Fuego province. Grytviken on South Georgia served as a Norwegian whaling station from 1904 to 1965 and now hosts a British Antarctic Survey research station and museum. Ernest Shackleton's grave is located in Grytviken cemetery, where he died in 1922 during his final Antarctic expedition. King penguin colonies on South Georgia number approximately 400,000 breeding pairs according to surveys conducted between 2013 and 2017, representing one of the largest king penguin populations globally. Tourist vessels departing from Ushuaia include South Georgia in extended Antarctic itineraries lasting 20 to 23 days, compared to standard Antarctic Peninsula trips of 10 to 12 days. The South Sandwich Islands consist of eleven volcanic islands stretching 350 kilometers in a north-south arc, all uninhabited and designated a marine protected area by the United Kingdom in 2012.
The Antarctic Peninsula lies 1,000 kilometers south of Ushuaia across the Drake Passage, with the Argentine claim to Antarctic territory extending from 25 degrees west to 74 degrees west longitude below 60 degrees south latitude. Argentina maintains six permanent research stations and seven summer stations on the Antarctic continent and surrounding islands, including Esperanza Base on the Antarctic Peninsula where the first documented Antarctic birth occurred in 1978. The Argentine Antarctic Institute in Buenos Aires coordinates scientific research programs through these stations, conducting studies in glaciology, marine biology, meteorology, and geology. The Antarctic Treaty of 1959, signed by Argentina as an original signatory, suspended all territorial claims for the treaty's duration while permitting scientific cooperation among nations. Tourist cruises from Ushuaia to the Antarctic Peninsula operate from November through March when ice conditions permit navigation through the Drake Passage, a crossing that takes 36 to 48 hours depending on sea state. The Antarctic Peninsula shares wildlife species with southern Patagonia, including Weddell seals, leopard seals, and multiple penguin species that also inhabit coastal Argentina from Peninsula Valdés southward.
The Lake District region centered on Bariloche connects overland to Chilean destinations through multiple Andean passes that remain open seasonally. The Cardenal Antonio Samoré Pass carries National Route 231 from Villa La Angostura to Osorno, Chile, at 1,314 meters elevation, remaining open year-round except during severe winter storms. The lake crossing route from Bariloche to Puerto Varas operates from September through April, combining boat transport across Lago Nahuel Huapi, Lago Frías, and Lago Todos los Santos with bus segments, totaling 12 hours transit time. Parque Nacional Vicente Pérez Rosales in Chile shares the southern Andes forest ecosystem with Argentina's Nahuel Huapi National Park, both protecting Nothofagus forests and volcanic landscapes. Puerto Varas and Puerto Montt in Chile serve as access points to Chiloé Island, located 100 kilometers west of the Argentine border and known for wooden churches designated UNESCO World Heritage Sites in 2000. The Futaleufú River, considered among the world's premier whitewater rafting destinations, flows from Argentina into Chile through Chubut province, accessible from the Argentine town of Trevelin.
The wine regions of Mendoza connect to Chilean wine valleys across low Andean passes where viticulture occurs on both sides of the mountains at similar latitudes. The Maipo Valley in Chile lies directly west of Mendoza across the Andes, both regions producing Malbec, Cabernet Sauvignon, and Carmenère at elevations between 600 and 1,500 meters. The Casablanca Valley in Chile sits 100 kilometers west of Santiago at Pacific coastal latitude, specializing in Sauvignon Blanc and Chardonnay, while comparable cool-climate viticulture in Argentina occurs in the Uco Valley at 1,200 to 1,600 meters elevation. The Colchagua Valley in Chile parallels the latitude of San Rafael in Mendoza province, both regions established by Spanish colonists in the 18th century and expanded by European immigrants after 1850. Cross-border wine tourism routes operate between Mendoza and Santiago, utilizing the Cristo Redentor tunnel that remains open to commercial traffic year-round with occasional closures during heavy snowfall from June through August.
The Atacama Desert in northern Chile shares geological characteristics with the Puna de Atacama in Argentina, both regions characterized by salt flats, volcanic peaks above 5,000 meters, and annual precipitation below 100 millimeters. San Pedro de Atacama in Chile sits 200 kilometers west of the Argentine border with Salta province, both areas offering access to high-altitude desert landscapes. The Salar de Atacama in Chile lies at 2,300 meters elevation and covers 3,000 square kilometers, while Salinas Grandes in Argentina spans 212 square kilometers at 3,450 meters elevation. El Tatio Geysers in Chile, located at 4,320 meters elevation, share the same volcanic system with geothermal areas in Catamarca and Salta provinces where mineral hot springs occur along the Andean volcanic arc. The town of Jama Pass connects Jujuy province to the Atacama region via National Route 52 at 4,200 meters elevation, the primary route for traffic between northwestern Argentina and Chilean ports.
The Strait of Magellan separates mainland South America from Tierra del Fuego, with Argentine territory occupying the eastern half of the main island and Chilean territory covering the western portion and surrounding islands. Punta Arenas in Chile serves as the administrative center for the Magallanes region, located 250 kilometers northwest of Ushuaia across the strait. Ferry services connect Punta Delgada in Argentine Tierra del Fuego to Bahía Azul in Chilean Tierra del Fuego, crossing the Primera Angostura narrows in 20 minutes. The Darwin Range in Chilean Tierra del Fuego extends eastward into Argentine territory, forming a continuous mountain system that includes peaks above 2,000 meters covered by the Cordillera Darwin Icefield. The Beagle Channel forms the southern boundary of the main Tierra del Fuego island, with both Argentine and Chilean settlements along its shores including Ushuaia and Puerto Williams respectively. Puerto Williams in Chile, located on Navarino Island, lies at 54.93 degrees south latitude, approximately 50 kilometers south of Ushuaia across the Beagle Channel.
The city of Punta Arenas provides access to Torres del Paine National Park in Chile, located 300 kilometers north of the city and established in 1959. Torres del Paine receives approximately 300,000 visitors annually according to CONAF statistics, comparable to visitor numbers at Los Glaciares National Park in Argentina. The granite towers that give the park its name rise 2,500 meters above sea level, formed by glacial erosion over the past 12 million years. El Calafate in Argentina lies 250 kilometers northeast of Torres del Paine, with organized tours crossing between the two destinations via the Río Turbio-Puerto Natales border crossing. The Southern Patagonian Ice Field extends across both nations, covering approximately 16,800 square kilometers with glaciers draining both eastward toward Argentina and westward toward Chilean fjords. Grey Glacier in Torres del Paine and Perito Moreno Glacier in Argentina originate from the same ice field, with Perito Moreno covering 250 square kilometers and Grey Glacier spanning 270 square kilometers.
Puerto Natales in Chile serves as the gateway to Torres del Paine and connects to El Calafate via a 270-kilometer road route through the Patagonian steppe. The Cueva del Milodón near Puerto Natales preserves the site where in 1895 Hermann Eberhard discovered remains of the extinct ground sloth Mylodon darwinii, a species that inhabited Patagonia until approximately 10,000 years ago. The Magallanes region of Chile and Santa Cruz province in Argentina share similar late Pleistocene paleontological records, with megafaunal remains documented at multiple cave sites along the Andean foothills. Road access between Río Gallegos in Argentina and Punta Arenas requires crossing Chilean territory via National Route 9 and Chilean Route 255, a distance of 260 kilometers primarily across flat steppe terrain.
The Carretera Austral in Chile runs 1,240 kilometers from Puerto Montt to Villa O'Higgins, paralleling the Argentine border through remote Patagonian territory. Multiple border crossings connect the Carretera Austral to Argentine towns including Coyhaique to Río Mayo, Chile Chico to Los Antiguos, and Villa O'Higgins to El Chaltén via seasonal boat transport across Lago O'Higgins/San Martín. Los Antiguos in Santa Cruz province sits on the southern shore of Lago Buenos Aires, called Lago General Carrera on the Chilean side, where the lake covers 1,850 square kilometers across both nations. The Marble Caves (Cuevas de Mármol) in Chilean waters of Lago General Carrera lie 5 kilometers from the Argentine border, accessible by boat from Puerto Río Tranquilo. The Northern Patagonian Ice Field in Chile covers 4,200 square kilometers approximately 150 kilometers west of the Argentine town of Perito Moreno, with limited overland access from either nation.