 It was built by Cardinal Cisneros who commissioned architect Pedro de Gumiel to design.The foundation stone was laid in 1499, the Saint Ildefonsus` Chapel was completed in 1510; in 1516 began construction of the "Paraninfo" (Auditorium) and in 1537 Rodrigo Gil de Hontañón designed the main façade.Although most of the work had been carried out by 1617 when Juan Gómez de Mora redesigned the courtyard (Thomas of Villanova's courtyard), the construction was not finished until the second half of the 17th century.