Cabecera municipal
Municipalities (municipios in Spanish) are the second-level administrative division in Mexico, where the first-level administrative division is the state (Spanish: estado). There are 2,438 municipalities in Mexico, with an average population 45,616. The internal political organization and their responsibilities are outlined in the 115th article of the 1917 Constitution and further expanded in the constitutions of the states to which they belong.
All Mexican states are divided into municipalities. Each municipality is administratively autonomous; citizens elect a "municipal president" (presidente municipal) who heads an ayuntamiento or municipal council, responsible for providing all the public services for their constituents. This concept, which originated after the Mexican Revolution, is known as a municipio libre ("free municipality"). A municipal president heads the ayuntamiento (municipal council). The municipal president is elected by plurality and cannot be reelected for the next immediate term. The municipal council consists of a cabildo (chairman) with a síndico and several regidores (trustees).
If the municipality covers a large area and contains more than one city or town (collectively called localidades), one city or town is selected as a cabecera municipal (head city, seat of the municipal government) while the rest elect representatives to a presidencia auxiliar or junta auxiliar (auxiliary presidency or council). In that sense, a municipality in Mexico is roughly equivalent to the counties of the United States, whereas the auxiliary presidency is equivalent to a township. Nonetheless, auxiliary presidencies are not considered a third-level administrative division since they depend fiscally on the municipalities in which they are located.
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