León Cathedral, dedicated to Saint Mary, mother of Jesus, is known as the Pulchra Leonina and is a masterpiece of the Gothic style of the mid-13th century.

In the Main Chapel, there is an altarpiece by Nicolás Francés (15th century) and a silver urn containing the relics of San Froilán, the town's patron saint, made by Enrique de Arfe.

There are almost 1,500 pieces, including 50 Romanesque sculptures of the Virgin, dating from prehistoric times to the 18th century (Neoclassicism) with works by Juan de Juni, Gregorio Fernández, Mateo Cerezo, a triptych of the School of Antwerp, a Mozarabic bible and numerous codices.

Little remains of these primitive buildings, only some vestiges of mosaics, roof tiles (tegulas), and ceramics, displayed today at the cathedral museum.

King Ordoño II, who had occupied the throne of Leon in 916, defeated the Arabs in the Battle of San Esteban de Gormaz in 917.

The temple was guarded and governed by monks of the Order of St. Benedict, and it is likely that its structure was very similar to many others existing during the Leonese Mozarabic period.

With the help of the infanta Urraca of Zamora, the first-born daughter of the king, begins the construction of a second cathedral, according to the aspirations of the city and the Romanesque style.

Although all of it was executed within the international currents of the Romanesque, contemplating what has survived of its statutory, we can find out that it had an indigenous character, still using the horseshoe arch, at least as a decorative form.

When the last proprietary king of León, Alfonso IX, accedes to the throne, the city and in the kingdom witness an important change in society, artistic creativity, and cultural development.

Under the pontificate of Bishop Martín Fernández and the support of King Alfonso X de Castilla, this new cathedral became entirely Gothic.

Like most French cathedrals, León was constructed with modular geometry based on the triangle (ad triangulum), whose members related to the square root of 3, to which the totality of its parts and the whole respond.

In addition to its layout, the Cathedral of Leon is also inspired by that of Rheims in its structure, the form of the chapels of its ambulatory (in this case polygonal), and the development of its transept.

Furthermore, the subtlety of its style was a challenge to its material; its numerous supports were extremely fragile, the lines are reduced to total optimization, in such a way that various architects of the time questioned the cathedral's ability to remain standing.

Also in this style was the library, currently the Chapel of Santiago, built by Juan de Badajoz el Viejo at the end of the century.

In the sixteenth century, Juan de Badajoz started the addition of non-Gothic elements with the construction of a plateresque gable in the Western façade, too tall and heavy.

This addition damaged the delicate balance of the whole building, causing cracks in the southern façade that needed restoration in the end of the century, including a new gable.

In the eighteenth century, Joaquin de Churriguera tried to improve stability by adding four pinnacles around the dome, but this caused further damage.

Madrazo's successors, Demetrio de los Ríos and Juan Bautista Lázaro, kept removing alien elements, like the plateresque gable in the Western façade, and replacing them with Neo-Gothic designs.

A fire caused by lightning consumed the rooftop on May 27, 1966, but the structure suffered no serious damage (thanks, partly, to the decision of not using too much water to put out the blaze).

This type of construction used to have an odd number of naves (three or five) supported by quadripartite, sexpartite, tercelet, fan, or star rib vault.

The main façade is generally structures in three flared openings, consisting of archivolts, jambs, and framed in a gable, a gallery of Old Testament kings, a large rose window (in the central nave), an andito (space through which the façade is accessed to perform possible reforms), and by two towers of different characteristics (roofed or not with an arrow-shaped pinnacle).

The cathedral shows macrocephaly, that is a roof larger than usual (the width of the transept in this case), which takes away some depth and perspective but instead provides more space for worshippers; being on the Way of Saint James, its influx is greater than other churches.