Chalcatongo de Hidalgo

Mixtec speakers call this place Ñuundaya, glossed as "place of the underworld", and also Xinivi or Ñuu Ndeyá. It sits at about 2,450 m in the foothills of the Sierra Madre del Sur, in the Tlaxiaco district. As a settlement it was founded in 1773. The 2020 census counted 2,737 people in the town; the 111 km² municipality holds 9,035 people in 27 localities, the largest after the centre being Progreso (1,239) and Chapultepec (636).

The municipal name is translated from Mixtec as "town that abounds". The land is mountainous, from 1,300 to 3,000 m (average about 2,556 m), with named peaks: Yuku Sutu, Yuku Kuan, Yuku Iñu and Yuku Chayu. The climate is cold and dry. Pine, oak, ash and fruit trees such as peach, pear and apple grow here, and the hills hold hawks, swallows, opossums and deer. The Ciénega area has several wells, the largest of them, Minija'a, supplying the town centre.

The place also appears in the ancient history of the Mixteca: the Codex Bodley, a Mixtec manuscript, records rulers of Chalcatongo. Today it is a seat in the Mixteca Alta, about 243 km by road from Oaxaca city. Former governor Ulises Ruiz Ortiz was born here.