The current church was built in 1612 by Augustinian friars to replace a wooden chapel.

It was damaged by fire in 1843 and was restored from 1873 to 1880 by the Obras Publicas under Engineer Antonio de la Camara and Father Santiago Muniz.

[3] It also has an unusual two-storey façade, supported by two pairs of columns on each side of the arched entrance.

The top of the façade holds a recessed niche that showcases the image of the city's patron saint, San Guillermo el Ermitaño.

[3][4] It is made of locally manufactured bricks joined by molasses and juice of sablot leaves[4] mixed with lime and sand, and reinforced with four massive columns on each corner and a winding stairway leading to the belfry.