At the eastern extremity of the Cathedral, behind the Capilla Mayor and projecting beyond the general outline, is the chapel of San Ildefonso. Erected by Archbishop de Rada, it remains the last important middle-pointed feature of the building, though considerably modified by Cardinal Albornoz in the latter part of the fourteenth century. It is eight-sided, and has beautiful traceried windows, and arches richly moulded and decorated. In arched recesses, beneath gabled and pinnacled canopies, are the tombs of Cardinal Albornoz, and several members of his family. There is much beautiful detail on the tomb of Don Iñigo de Mendoza, who fell at Granada in 1491; and the sepulchre of the Bishop of Avila by Tejada is a noble temple of the plateresque. The altar is modern. St. Ildefonso was the prelate who distinguished himself by his advocacy of the doctrine of the Immaculate Conception. In return he is said to have received signal marks of favour from the Blessed Virgin, who invested him with a cassock, came down to attend Matins in his company, and so forth. To the north of this chapel is the larger Capilla de Santiago, likewise projecting beyond the original ground plan, and dating from 1435. It was built by order of the Great Constable, Alvaro de Luna, to be the place of sepulchre of himself and wife, on the site of an earlier chapel dedicated to St. Thomas à Becket. The plan is similar to that of the last chapel described. Outside, the flat-pitched tile roof is finished with a battlement and circular turrets at the angles. The most conspicuous features of the chapel are the tombs, in Carrara marble, of the Constable Alvaro de Luna and his wife Doña Juana Pimentel. The Constable is shown in full armour, and at each corner of his tomb kneels a knight of Santiago, of which order he was Grand Master. Four Franciscan monks attend on his lady. In niches in the wall repose kinsmen of the ill-fated Constable, the tombs all having been executed by permission of Isabel the Catholic, by Pablo Ortiz in 1488, thirty-five years after De Luna’s death on the scaffold at Valladolid. The tombs designed for the Constable in his lifetime were to have been furnished with life-size figures in bronze, which, by mechanical contrivance, were to have risen each time Mass was celebrated, and to have remained during the service in a kneeling posture. These figures were destroyed by the Infante Don Enrique, and the bronze was used by Villalpando for the pulpits in the Capilla Mayor. The retablo of the High Altar reveals the portraits of the founder and his wife by Juan de Segovia. “The chapel,” says Mr. Street, “bears evidence in the ‘perpendicular’ character of its panelling, arcading and crocketing, of the poverty of the age in the matter of design. At this period, indeed, the designers were sculptors rather than architects, and thought of little but the display of their own manual dexterity.”