Covering the southern half of South America, Argentina features some of the world’s tallest mountains, including Aconcagua, which reaches 22,834 feet. A home to almost 40 million people, Argentina’s capital and largest city is Buenos Aires. Bordered by Bolivia, Paraguay, Uruguay, and Brazil, Argentina features six major regions: Cuyo and the Andean Northwest, Mesopotamia and the Northeast, the Chaco, the Pampas, Patagonia, and Tierra del Fuego. Spanish is the official language.