It is the most important monument of the town. It was erected in 1779, in a pure neoclassical style, by the architect Ventura Rodríguez -which links it to the temples of Santa Fe and Vélez de Benaudalla-, and paid for by the V Marquis of Algarinejo.
The building stands on the site of a primitive church, also dedicated to Santa María la Mayor, which existed in Algarinejo from the 16th century until 1772, when it was demolished for the construction of the new temple, according to the Book First Old from the parish archive.
The new church would take fourteen and a half years to erect, from 1779 to 1794. The project manager was Ventura Rodríguez, municipal architect of Madrid, and with works as emblematic as the Cibeles fountain or the dressing room of the Virgen del Pilar in Zaragoza. . He was also director of the architecture section of the Academy of San Fernando from 1752. The architects Francisco Aguado and Francisco Quintillán intervened in the direction of the work.
The famous architect projects a large building, governed by austerity and scrupulous symmetry, with an absence of superfluous decorative motifs. It has a Latin cross plan, with a large dome on the transept made of brick, and it has three naves. The central nave is the most important, both for its height and its width. It is separated from the side naves -in which several chapels open- by simple pillars and semicircular arches, and is covered by a semi-barrel vault with transverse arches. The main altar is square in plan, covered with a half-barrel vault and topped by a semicircular triumphal arch. It is presided over by a tabernacle with Doric columns. On both sides of the main altar is the sacristy and the chapel of Nuestro Padre Jesús Nazareno.
The interior of the church was covered by a layer of plaster, apparently as a disinfectant against outbreaks of epidemics. It remained like this until the 80s when it was restored. At present the interior of the temple is practically bare, except for some frames in the windows, doors, pediments and cornices. It combines semicircular openings, blind oculi and lintelled windows. The tower that appears behind the head of the temple stands out.
On the outside, a sundial stands out, with a circular stone sphere, embedded in one of its corners, dating from the year 1790.
The church has three portals made of hewn stone. The main façade, facing south, is located at the foot of the temple and is preceded by two stands. It is arranged by means of a lintelled door, framed by a molding and a curved pediment.
Above, a blind oculus and, finally, a triangular pediment resulting from the gabled roof of the nave, pierced in its center by a lintelled opening.