The pre-Romanesque basilica
At the beginning of the 9th century, Alfonso II ordered the construction of a church that would serve as a pantheon to the north of the basilica dedicated to the Savior and the Holy Apostles. These two temples would form a complex with the church of San Tirso and the Holy Chamber.
The basilica, dedicated to Santa María and with altars dedicated to San Julián and San Esteban, described a basilica plan with a straight triple head. At the foot would be the royal tribune on the space destined for the pantheon of the Asturian monarchy. This building, which was the first pantheon of the Spanish monarchy, served as a model for the one built shortly after in León dedicated to San Isidoro.
The baroque chapel
At the end of the 17th century, the Basilica of Santa María was in a dilapidated state, which is why Bishop Fray Tomás Reluz (1697-1706) commissioned Bernabé de Hazas to build a new one. Counting on royal patronage, Hazas designed a temple larger than the original one, describing a basilica floor plan, with three naves separated by thick pillars, a transept covered by a dome on a drum and a straight head. The old late Gothic doorway of the northern transept was integrated into the new church and serves as a link between it and the cathedral.
The elements of the roof display profuse plant and heraldic decoration, on the pendentives that support the drum of the dome, the busts of kings Fruela I, Alfonso II, Ordoño I and Alfonso III were carved.
At the foot of this chapel, above the entrance door, there are three heads of a Calvary, sculpted in stone and dated to the end of the 12th century due to their parallelism with those preserved in the Holy Chamber.
The royal pantheon
The royal pantheon is located in the last section of the north nave, there, behind a grill topped by the shield of Felipe V, are the six sarcophagi that guard the remains of various kings, queens and princes. In the center is the early Christian sarcophagus of the young Itacio, from the 5th century, reused during the time of the monarchy, decorated on its lid with scrollwork, a chrismon with facing birds and chalices.
The late Gothic portal
The late Gothic portal preserves a group of high-quality sculptures with Flemish roots. The center of the composition is occupied by the figure of the risen Christ accompanied by two angels carrying instruments of passion. In the archivolts are the sculptures of Santiago, San Pedro, San Pablo and San Andrés, as well as the four evangelists, prophets and kings of the Old Testament. In the mullion, in the 16th century, a polychrome Virgin of the milk was placed in the 18th century.
The main altarpiece is the work of the sculptor Antonio Borja (1661-1730). It was built between 1715-1719 using the stipes supports for the first time in Asturias. It is dedicated to Our Lady of Battles and the reliefs depict various scenes from the life of the Virgin. In the attic, and flanking the central scene where the Assumption-coronation of the Virgin is represented, are the busts of the holy kings Hermenegildo and Fernando III.
The altarpiece of the Virgen de la Luz is dated 1552 and originally formed part of the altar in the rear choir of the main nave. It was transferred to this chapel with the dismantling of the late Gothic structure in 1901. In it, the central image stands out, the Virgen de la Luz, a Mannerist sculpture attributed to Manuel Álvarez.
On the sides of this altarpiece are the stone sculptures of Saint Peter and Saint Paul, carved around 1733-1737 and also coming from the retrochoir.