This chapel was erected in it’s present form for the burial of the distinguished Cardinal Gil Carrillo de Albornoz (†1364), pontifical legate, minister of Alfonso XI and founder of the Spanish College of Bologna and it takes up the central part of the apse. It is octagonal shaped in a Gothic style, with tracery vaulting and golden lobes on the ribs. It also contains the coat of arms from Albornoz.
In the middle of the chapel we can find the founder’s sepulchre. Cardinal Marcelo González Martín (†2004) was recently buried between the grilles and the sepulchre of Albornoz. The central altarpiece at the back was built in 1780 by Ventura Rodríguez and shows the Descension of the Holy Virgin to put the chasuble on Bishop Saint Ildephonsus. At the right of the altar we find the sepulchre of the Bishop of Ávila, Don Alonso Carrillo de Albornoz. It was made in a Plateresque style by Vasco de Zarza in 1515. As early as the times of Archbishop Jiménez de Rada (1215), the chapel was already dedicated to Saint Ildephonsus.