The monastery of San Guillermo Abad is located in Totolapán and built by the Augustinians in 1553. Its cloister is small even though its walls and buttresses are very heavy. The corner chapels in the atrium are still intact and there are a number of notable oil paintings and an old organ in the choir of the church. There is also an outstanding two-color frieze in one of the rooms on the first floor of the cloister near the main façade of the church. This and other mural work in the inner passageways of the cloister have been recently restored. Stone arcades and pillars are decorated with small stones set with cement.