Parroquia de San Juan Bautista
One of the earliest churches built in New Spain, this huge and striking church dates to 1527, although construction wasn't completed until 1550, and it's been rebuilt and extensively remodeled at various times (its spire had to be repaired after it was badly damaged in the city's 2017 earthquake). The interior is quite spectacular, with priceless artwork and a gorgeous vaulted ceiling. Next door, the cloister of the former convent is a peaceful spot to relax and reflect.