I visited Mexico between February and April 2019. I visited most WH colonial towns around Mexico City and San Miguel was the third one.

Even though really few monuments are remarkable, I quite enjoyed San Miguel. The little cobblestone street with orange or pink houses are really charming and la Parroquia de San Miguel Arcangel is very beautiful. Other churches, especially around Plaza Civica, are interesting as well. However, this city is more enjoyable for its atmosphere. When I was there, pre-easter celebrations were happening with kids running around and crushing colorful eggs filled with confetti on each other! It was just good to sit there and smile with the happy crowd.

I also visited el Santuario de Atotonilco. Getting there by public bus is easy, but the schedule is highly unpredictable. The first day I tried to go there, I waited for the bus at the place and time I was told by the tourism office, but the bus never showed up. I tried again the next day after making sure I was right about where and when to wait for it. This time was fine as the bus came and was almost full. The same problems happened when I tried to come back from the sanctuary. I've been told two different times for the bus to leave, so I just waited there. It finally came and left on a third different time! At least, buses seem to go by every hour, so you shouldn't be waiting for long. Anyway, it is really worth going there. Even if the visit is quite short and there's nothing else to see in Atotonilco, the paintings are worth the disproportionated travel/waiting vs visit time. Make sure you pay the small fee to enter the room on the left where the nicest frescos are situated.

Even if it's not within the WH zone, I want to mention el Jardin Botanico El Charco del Ingenio. This birder's paradise northeast of the city was my highlight here! There are a lot of trails and nature there is generous! It is also worth mentioning that you can easily visit el Templo de San Juan de Dios, part of Camino Real WHS. You should also hike to the mirador up Parque el Chorro for a nice view of the town. San Miguel is perfectly located between Guanajuato and Querétaro, but you can also travel here to and from Mexico City, Guadalajara, and Léon.