The church of San Juan Bautista is a Romanesque church located on one side of the Plaza Mayor. The name San Juan is due to San Juan Bautista and the Puerta Nueva was a doorway when the neighbouring wall passed close to the square. It dates from the middle of the 12th century. In 1961 it was approved as a Historical Monument. In one of its corners, on the outside, there is a modern statue dedicated to the Merlú, a work that was erected in 1996 by the Zamora sculptor Antonio Pedrero Yéboles.

This church, located on the western side of the main square, was built in the second half of the 12th century and part of the following century, next to the so-called Porta Nova, the easternmost gate of the first walled enclosure, opened in 1171 to connect the primitive enclosure with the suburb. The proximity of this gate led to this church being known by the title of San Juan de Puerta Nueva. During the 17th and 18th centuries, the festivity of the Forty Hours was celebrated during the carnival season. This celebration was very popular and lasted three days.

The building has undergone numerous repairs, transformations and losses over time. Rodrigo Gil de Hontañón, a master builder, was put in charge of the refurbishment. In 1559, the tower and a large part of the roofs collapsed, being rebuilt in 1579 and replaced by a Mudejar framework, which has been hidden by a lunette vault from the 18th century, while all the perimeter walls were built.

At the end of the 19th century, the Town Council planned the widening and alignment of the Plaza Mayor, which included the demolition of the church, but this was not carried out due to the energetic protest of the bishop of the diocese. However, in 1905 it was forcibly expropriated and two years later the cloister attached to the northern wall was demolished. Thanks to the latest restoration carried out by Bellas Artes, it has been completely exempted, with the demolition of all the adjoining constructions and other false constructions that almost completely concealed its volumetry.