Hoy no circula

Entities participating in this program, Federal District, Estado de Mexico, Hidalgo, Puebla, Tlaxcala.

I could be totally wrong about this. After reading over the information provided by the previously mentioned website called Hoy No Circula where all the information can be found it is my understanding that the states mentioned in the quote above can participate in the emissions testing program to get a hologram which loosens the restrictions on vehicles which can pass the emissions tests. The restrictions do not appear to be in these areas but these states are listed as being those which can participate in the emissions program. I think perhaps this is because people who live in these areas may have to commute to work in restricted areas - I am just guessing at this but after many readings this seems to be the only conclusion I can come to. They can take an emissions test and if they pass they get a hologram which can be seen on the vehicle.

Also - - - the term San Juan Teotihuacan de Arista seems to have been universally shortened to just Teotihuacan and most use that name - I find using San Juan is rarely used because there must be a million other San Juans - Teotihuacan is much more specific.


https://en.wikipedia.org/wiki/Teotihuac%C3%A1n_(municipality)

San Juan Teotihuacan de Arista, State of Mexico, Mexico

Teotihuacán is a town and municipality located in the State of Mexico. It is in the northeast of the Valley of Mexico, 45 km northeast of Mexico City and 119 km from the state capital of Toluca. Teotihuacan takes its name from the ancient city and World Heritage site that is located next to the municipal seat.

"Teotihuacan" is from Nahuatl and means "place of the gods." In Nahua mythology the sun and the moon were created here.

As municipal seat, the town of San Juan Teotihuacán is the local governing authority for about 115 other named communities[20] with a combined territory of 82.65km2.[1] A little under half the municipality’s population lives in the town proper.[20] The municipality borders the municipalities of

Temascalapa,

Acolman,

Otumba de Gómez Farías,

San Martín de las Pirámides

and Tecámac.[1]

TECAMAC is the only municipality listed in the restricted zone but some routes could require that you pass through this area to get to Teotihuacan.

Based on the above information and other information about how the Spanish system of municipios is set up the name Teotihuacan is used for both the area specific to the place we would call a town - but also includes some 115 other communities around the main town. This often confuses people from the US about what is called a town in Mexico. I think in the US we would call it a county. So you would want to think of a municipio as a county - which might make it easier to understand what is meant by municipio or municipality.