It occupies a section of the nave. Attached to its back part there is a small sacristy which shares another section of the nave with the rear framework of the reredos. The main chapel is closed by three gilded 16C iron screens, that on the main side being a work of art by the Dominican monk Francisco de Salamanca who finished it in 1529. It has four horizontal sections and four vertical divisions with traceried decoration on top. The frieze and top decoration depict scenes of the Gospel. The pulpits flanking the presbytery are also by Francisco de Salamanca. Made of gilded iron they were finished in 1532, with that on the left showing the figures of the Four Evangelists and that on the right four scenes from the life of St Paul.

The wrought-iron screens on the sides are of a desegn similar to the main screen although it was the craftsman Sancho Muñoz, who began them in his workshop in 1518, and Diego de Huidobro and juan de Conillana who finished them in 1522.

The solemn main reredos stands in front of the presbytery. Ir is considered the lasgest in Chistendom and was completed in succesive stages in the course of almost a century. The first design was by the Flemish or German sculptor Pyeter Dancart who planned a reredos in 1482 which was to be twenty metres high and eighteen metres wide, have four horizontal sections with a pradella and seven vertical divitions. Dancart conrinued working on the reredos until 1488 when it seems he died. As from 1497 Master Marco of Flemish origin took charge until 1505. Between 1507 and 1508 the sculptor Pedro Millán is found to be working on the reredos. In his last year he was replaced by Jorge Fernandez Alemán who, with his brother, the painter Alejo Fernández, worked on it until 1529, when the first building stage was concluded.

The second stage began in 1550 when the chapter decided to add two side divisions at right angles to the main part. The work was carried out by Roque Balduque, Juan Bautista Vazquez el Viejo and Pedro de Heredia and was completely finished in 1564.

The reredos has a total of forty-four reliefs and over two hundred figures of saints distributed over the pilasters which structure the reredos. Above a large, projecting canopy with octogonal caissons there is a beam with a Pietá Flanked by the apostles in its centre, a work of art by Jorge Fernández. At the top there is a huge 14C Gothic Crucifixion which had been preserved by thr Cathedral and which the chapter decided to place above the retable. The cross in the Crucifixion is traditionally known as Cristo del Millon, but there is no reason justifying the name.

The reliefs of the predella are the oldest of the reredos and depict three scenes of the saintly martyrdom. There is also a view of Seville with las Santas Justa y Rufina, and another one of the Cathedral itself with San Isidoro and San Leandro. In its centre there is a magnificent Gothic sculpture of La virgen de La Sede, which is made of wood and is silverplated. It most probably dates from the second half the 13C.

From right to left, the first section of the reredos shows The Embrace of St Joachim and St Ann, The Birth of the Virgin, The Annunciation, The Birth of Christ, The Slaughter of the Innocents, The Circumcision and The Epiphany.

The second section depicts The Presentation of Jesus in the Temple, Christ´s Baptism, The Raising of Lazarus, The Assumption, Christ´s Entry into Jerusalem, The Last Supper and Christ´s Agony in the Garden.

In the third section: Christ´s Arrest, The Flagellation, The Crowning of Thorns, The Resurrection, Ecce Homo, On the Way to Calvary and The Despoliation.

In the fourth section: The Burial of Christ, The Three Marys at the Holy Sepulchre, Mary Magdalen at the Feet of the Risen Jesus, The Ascension, Christ´s Descent to Limbo, The Supper at Emaus and The Coming of the Holy Ghost.

On the sides of the reredos from the bottom to the top, on the left there are the Creation of Eve, from which her figure is missing as it was stolen from the reredos, The Flight to Egypt, Chris among the Doctors, The Transfiguration and Mary anointing Christ´s Feet. On the right there are The Original Sin, The Last Judgement, The Miracle of the loaves and the Fishes, The Cleansing of the Temple and The Conversion of St Paul.

The pillars framing the whole of the reredos show eight reliefs representing the kings of Israel and Judah.

The gilded silver tabernacle on the altar of the Main Chapel is important. It was made by the silversmith Francisco de Alfaro who finished it in 1596. The silver lecterns on the sides of the altar are also by Alfaro.

The exterior walls of the Main Chapel are decorated with a profusion of statues of saints, bishops and kings on consoles and under baldacchinos. They date from between 1517 and 1575 and were carried out seccessively by Miguel Florentín, Juan Marín and Diego de Pesquera.