San Simón Tlatlahuquitepec

San Simón Tlatlahuquitepec is the most populous locality in the municipality of Xaltocan, with 3,217 residents at the 2020 census, ahead of the municipal seat itself, which had 1,328. It sits at 2,541 metres above sea level in northern Tlaxcala and has grown from 808 people in 1900 to 1,582 in 1970, 2,292 in 2000 and 2,817 in 2010. The name comes from Nahuatl: tlatlauhqui (red or ruddy), tepetl (hill) and the locative -co, and is translated as on the red hill. The patron is Simon the Apostle, titular of the church, which appears in Wikimedia Commons photographs with a multi-tiered tower, a dome and an orange-trimmed façade.

The village is ringed by small communities: Tlatelpa and Tepetexco a little over 1 km to the southeast; La Ascensión Huitzcolotepec, 2.4 km to the northeast, with 884 residents; the municipal seat Xaltocan about 3 km to the southwest; and Topilco de Juárez, 3.2 km away, with 2,385. To the south and southwest are hills of 2,400 to 2,600 metres, such as Cerro Cenizo (2,509 m), Cerro El Fuerte (2,575 m) and Cerro Ostol (2,474 m), 5 to 6 km off.

Because of the altitude the climate is among the coolest in the region: a mean of about 13.4 °C, January the coldest month (11.1 °C) and May the warmest (15.7 °C), and about 695 mm of rain a year spread over some 214 days with precipitation.