Although San Miguel was founded in the 1540s, the town you see today dates mainly from the 18th century, when it thrived as a staging post on the so-called Ruta de Plata (Silver Route) and as a centre for fabric manufacture. Most churches have elaborate facades in the late baroque style known as Churrigueresque, but sometimes with semi-concealed pre-Columbian motifs introduced by native craftsmen. On the other hand, the signature parish church (La Parroquia) has a curious 19th century Gothic exterior that some regard as Disneyesque! There are also a number of fine mansions with imposing facades, although few of these are accessible to the public.

San Miguel went into decline in the early 20th century and there are few buildings from that period. One exception is the former fabric factory, Aurora, now given over to upscale boutiques and galleries. Most of the post-World-War-Two development of homes for foreigners is pseudo colonial, with a minority built in the so-called 'Mexican Modern' style. Boveda ceilings are ubiquitous, even though these are said not to be traditional.

San Miguel was given a UNESCO World Heritage designation in 2008 and officially there are restrictions on what can and cannot be built in the blocks that make up the historic centre, as well as the colours that buildings can be painted.