The Temple of San Jerónimo Aculco is the main church of the town and parts of its old monastery date back to the 1540s when it was founded by the Spanish crown. Most of the church we see today dates from the mid-18th century. The façade proudly bears the so-called Tequitqui style. Also called the Tributary Baroque style, the terms generally refer to works of architecture and sculpture made under the direction of religious builders.

The church faces the main town square as is common with colonial era churches. It is somewhat more unusual in having the atrium more or less intact, and still walled off from the busier parts of the town center. Many nearby buildings are in some measure from the same mid-18th century period of construction.

The bell tower dates from 1900. This and the church and complex were badly damaged in a 1912 earthquake. The church is arguably most famous for the painting of Our Lady of Mount Carmel rescuing souls from purgatory. It dates from the late 18th century. A version of The Last Supper by Viceregal artist Miguel Cabrera can be seen within the old monastery to the south of the nave. This and paintings of Saint Anthony of Padua and the Czech Saint, John of Nepomuk can be seen in the former convent. The Jesuits are likely responsible for Mexican sacristies having more depictions of this Saint John than anywhere else in the world. In most of the rest of the world, he\'s depicted at the middle of bridges, a reference to wear he was martyred.

Of course, within the town, San Jerónimo has always faced competition from the Señor del Nenthé chapel. The Otomi name implies that he was found at the side of water, or a river. The Lord of Nenthé has been honored here in Aculco since at least 1702. This is especially true in times of drought. His chapel is roughly a ten-minute walk northeast of the main town square and the atrium of the San Jerónimo church.