San Juan Atzingo

San Juan Atzingo is the heart of the Tlahuica people, who call themselves and their language Pjiekakjoo, "what I am" or "what I speak". The village lies northeast of Ocuilan de Arteaga in the ranges that divide the Toluca valley from Morelos, surrounded by pine and sacred-fir forest that runs on toward the Zempoala hills, with maguey and pear trees along its lanes. It had 1,119 residents in 2020. Tlahuica, also called Atzinca or Ocuilteco, is a close relative of Matlatzinca in the Oto-Pamean branch and is seriously endangered: a 2011 study found 63 speakers across the village's five barrios, almost all aged 70 or over, yet San Juan is the one community where it is still a living household language.

The area's past runs from early Otomian peoples through the Mexica conquest of Ocuilan in the late 15th century to a colonial period that left few records; the 1790 census lists most villagers as hacienda day labourers. What sets the village apart today is its own self-government. A traditional authority settles disputes by negotiating between the parties, and mayordomías look after each saint through the year. The church keeps the sacred staffs of justice and a sacred teponaxtle drum carved with a feline head, brought out only on special dates: 31 January, Holy Week, 24 June (Saint John's day), changes of authorities, and a yearly ceremony to the Sun at the start of spring. On 5 June 2026, at the communal land office, INAH and the federal Ministry of Culture handed over an anthropological report on the Pjiekakjoo people's historical presence here, backing the community's land claim to some 18,000 hectares of forest.

Many families make a living from wood, building rustic furniture such as tables, chairs and beds, sold mostly at the furniture market of San Pedro Tultepec in Lerma.