in 1616 under viceroy Diego Fernandez de Cordoba with the objective of bringing water to the Sanctuary of Los Remedios from a spring at the village of San Francisco Chimalpa. This water was also used to irrigate fields in the villages of San Bartolomé, Santa Maria Nativitas and Santa Cruz. The aqueduct is mostly of clay pipes with two large spiral towers to release air. These towers flank the Sanctuary of the Virgin of Los Remedios and are nicknamed "caracoles" (snails) By 1764, the amount of water this system delivered was no longer enough and viceroy Joaquín de Monserrat had the arched system built, which was finished in 1765. Eventually, this system could not deliver water and became simply an architectural monument. Seventy five percent of the original surface of the park now has illegal settlements, including settlements which have been authorized by local authorities. While these settlements can be confiscated and destroyed under federal law, this has not happened. The federal environmental agency Profepa has received complaints about the most recent invasions into the park area, which as felled dozens of trees. The agency has responded with inspections of plans by a developer to build two subdivisions near the colonial era aqueduct to verify if the land is private or public. One reason for this is that the park lacks conservation plans, fences and other means to fend off development efforts. The illegal settlements and development have also affected adjoining ejido land that adjoin the park. This and the fact that housing is now starting to encroach the archeological zone has prompted the involvement of INAH and the organization of neighboring communities to protest. Towns and villages The largest localities (cities, towns, and villages) are: Economy Naucalpan is one of the most powerful municipalities in the country; in the area next to Mexico City there's many little and medium-sized businesses; such as pharmaceutical labs, spare parts businesses and chemical products and textile manufacturing factories. The commercial and services sector is important, in the last 40 years it's grown. Its thrive begun with the opening of the Plaza Satélite mall in 1971. In 2007 another mall was built: La Cúspide Sky Mall. According to the Reyes-Barreto-Rodríguez (2007) study of the wealth distribution in the State of Mexico, Naucalpan de Juárez in the year 2000 generated enough wealth to cover the necessities of their citizens twice, in contrast to other municipalities