Chile's capital is Santiago, with a population of over 15 million people. It has an area of 1,284,000 sq km, which is over 10 times the size of Ireland. Chile's highest mountain is Ojos del Salado, and its longest river is the Loa River. Chile's official name is the Republic of Chile and its official language is Spanish. Neighboring countries include Argentina, Bolivia, and Peru. Chile is the longest country in the world from north to south, stretching over 4,600 km along South America's western coast.