Mexico City, or the City of Mexico, is the capital and most populous city of Mexico. As an "alpha" global city, Mexico City is one of the most important financial centers in the Americas. It is located in the Valley of Mexico, a large valley in the high plateaus at the center of Mexico, at an altitude of. The city consists of sixteen municipalities . The 2009 estimated population for the city proper was approximately 8.84 million people, The Greater Mexico City has a gross domestic product of US$411 billion in 2011, making Mexico City urban agglomeration one of the economically largest metropolitan areas in the world. As a stand-alone country, in 2013, Mexico City would be the fifth-largest economy in Latin America—five times as large as Costa Ricas and about the same size as Perus. Mexico’s capital is both the oldest capital city in the Americas and one of two founded by Amerindians, the other being Quito. The city was originally built on an island of Lake Texcoco by the Aztecs in 1325 as Tenochtitlan, which was almost completely destroyed in the 1521 siege of Tenochtitlan, and subsequently redesigned and rebuilt in accordance with the Spanish urban standards. In 1524, the municipality of Mexico City was established, known as México Tenochtitlán, After independence from Spain was achieved, the federal district was created in 1824. After years of demanding greater political autonomy, residents were given the right to directly elect a Head of Government and the representatives of the unicameral Legislative Assembly by popular vote in 1997. Ever since, the left-wing Party of the Democratic Revolution has controlled both of them.