Ex Convento de San Agustín, Acolman

The Ex Convento de San Agustín in Acolman was built by Augustinian friars beginning in the 1530s-1540s as part of the early evangelization campaign that followed the Spanish conquest of the Basin of Mexico, and it stands close to Teotihuacan in a region that was densely settled by Acolhua and Nahua communities before and after contact. The monastery's plateresque facade, carved from grey stone, combines European Renaissance ornament with an austere, fortress-like massing typical of 16th-century conventos built to project both religious and defensive authority in newly converted territory. Its open-air atrial chapel and crenellated parapets are unusually well preserved examples of the atrium-and-posas layout used across central Mexico for mass outdoor evangelization of indigenous populations, since early converts often worshipped outdoors rather than inside enclosed naves. Inside, the cloister and church retain fragments of 16th-century murals in the grisaille style, along with later colonial religious paintings and sculpture documenting the transition from Augustinian mission to parish church. The complex suffered periodic flood damage from the nearby Rio San Juan Teotihuacan over the centuries, and restoration campaigns in the 20th century stabilized the structure and the interior murals, leading to its recognition alongside other early Augustinian and Franciscan monasteries on the slopes of Popocatepetl as sites of exceptional Renaissance-influenced monastic architecture in the Americas. Today the former monastery functions as a site museum, the Museo Virreinal de Acolman, displaying religious art and artifacts from the evangelization period alongside the architecture itself.