This monastery, situated east of the zócalo, and the attached church were built by Dominican priests between 1560 and 1588. The plateresque church facade has Dominican seals interspersed with indigenous symbols, floral designs and various figures, including the sun, moon and stars, animals, angels and the Virgin Mary. Upstairs, various cells house a bookstore, galleries and a regional history museum.

The monastery’s arched entryway is adorned with an elaborate seed mural of pre-Hispanic history and symbolism. Every year during the first week of September, local artists sow a new mural from 60 varieties of seeds.