Atlalco

The name comes from Nahuatl: atlalli, "irrigated land", with the locative -co. So it is the place of irrigated lands, a name that suits the local climate: warm and humid, with rain nearly all year and an average temperature around 22 °C. The community stands at about 309 metres in the Carso Huasteco ranges, and its water runs to the Calabozo river sub-basin.

It belongs to Yahualica municipality and had 679 residents in 2020 (347 women and 332 men), against 744 in 2010. It is not isolated: Oxeloco, with over a thousand people, lies 670 metres to the southwest; El Paraje is 780 metres west and Chiatitla a little over a kilometre east. Connectivity figures are low: a third of homes have a mobile phone and just over 1% have internet.

Two reference points: the seat, Yahualica, about 6.3 km southwest as the crow flies, and Santa Teresa, the municipality's largest locality, about 6.8 km northwest. Among the nearby hills is Tlatlapaya, at 773 m, a little over 4 km on foot to the west. There is another Atlalco in neighbouring Xochiatipan municipality, so it helps to say "Atlalco, Yahualica" when asking directions.