At one time merely a suburb of adjacent La Paz, Bolivia, on the Altiplano highlands, the city of El Alto (Spanish for The Heights) is today one of Bolivia's largest and fastest-growing urban centers. As of the 2001 census, the population was 649,958. In 2010, the population may be nearly 900,000, or more. The city contains La Paz's El Alto International Airport. El Alto is one of the highest major cities in the world, up to 4150 meters (13,615 feet) above sea level.