The Basilica of Our Lady of the Assumption (declared a Site of Cultural Interest with the category of Monument) began construction in 1492. The original church, smaller than the current one, underwent its first restructuring in 1560, when the central nave was placed perpendicular to its original orientation. In the years following 1614, the main chapel, the vault, and the roof were completed. By the end of the 17th century, however, the church was in ruins due to successive expansions of the church and its chapels, which had affected the foundations, leading to its closure in 1694. Its reconstruction, begun a year later, was undertaken by the City Council. The new church, notable for its Rococo-Baroque facade, suffered a fire in the mid-19th century, necessitating renovations, including the construction of its bell tower. The works were completed in 1873.

Its three-aisled floor plan also includes five side aisles and the sacristy. In addition to the main entrance, it has two side doors: the Door of Saint Peter on the left facade and the Door of Saint Mary on the right. The original altarpiece of the main altar was sold at the beginning of the 19th century to finance the renovation of the Basilica's floor and replaced by another made in 1911 by Sebastián Guillén and Manuel Carrillo (who also carved the pulpit in wood), which was destroyed during the Spanish Civil War. The current altarpiece was made by carpenters from Cieza in 1940 and completed with six panels depicting Marian themes in 2004. A valuable organ of great artistic and musical significance was recently installed in the choir loft.