Ecatepec, once officially San Cristóbal Ecatepec de Morelos, is a city and municipality in the State of Mexico. Both are usually known simply as "Ecatepec". The city is practically co-extensive with the municipality, with the city's 2005 population of 1,687,549 being 99.9% of the total municipal population of 1,688,258. The provisional population at the 2010 Census was 1,658,806. The city forms the most populous suburb of Mexico City.The name "Ecatepec" is derived from Nahuatl, and means "windy hill" or "hill devoted to Ehecatl". It was also an alternative name or invocation to Quetzalcoatl. "Morelos" is the last name of José María Morelos, a hero of the Mexican War of Independence.The municipality borders with Tecámac, Nezahualcóyotl, Acolman, San Salvador Atenco, Tlalnepantla and Distrito Federal. The area of this municipality is 155 km².Most inhabitants commute to Mexico City for work, and recently the Mexico City metro subway system was extended into Ecatepec."San Cristóbal" is the city's patron saint, whose feast day is celebrated on July 25 of each year.Points of interest include the newest Catholic Cathedral in Mexico, Sagrado Corazón de Jesús, several colonial era churches and the colonel edifice Casa de los virreyes.