The Altiplano (Spanish for "high plain"), Andean Plateau or Bolivian Plateau, in west-central South America, where the Andes are at their widest, is the most extensive area of high plateau on Earth outside of Tibet. The bulk of the Altiplano lies within Bolivian and Peruvian territory while its southern parts lie in Chile and Argentina. The Altiplano plateau hosts several cities like Puno, Oruro, Potosí, Cuzco and La Paz, the administrative seat of Bolivia. Northeastern Altiplano is more humid than the Southwestern, the latter of which hosts several salares, or salt flats, due to its aridity.