The Frissell Museum (a block west of the town entrance road, by the Mitla [1] town plaza) has been closed for several years due to earthquake damage. Thankfully, it is slated to be repaired and reopened in the near future, displaying its exceptionally fine artifact collection, including a host of finely preserved ceramic figurines, yet-to-be-deciphered Zapotec glyphs, and a Zapotec marriage certificate in stone.
Besides its collection, the museum’s historic venerable hacienda-style home is notable in its own right. From the mid-19th century, as the Posada La Sorpresa, it served as a lodging, owned and operated by the longtime local Quero family.
In 1950, they sold it to American artifact collector Ervin R. Frissell, who turned the hotel into both his home and a repository for his growing collection and that of his friend, Howard Leigh, noted scholar of Mixtec language and culture. Upon their deaths, the entire building and artifact collection passed to the University of the Americas.
Links:
[1] http://www.moon.com/destinations/oaxaca/the-oaxaca-valley/east-the-textile-route/mitla-archaeological-zone