Casón del Buen Retiro is one of two buildings that survived the destruction of the Buen Retiro Palace. Currently, it is the seat of the Museum Studies Center, the aim of which is research as well as training of experts in the field of art. The building also houses documentation, an extensive archive, as well as the library and conservation collections of the Prado Museum. In total, there are around 60,000 volumes and around 700 journal titles. In 1987, digitization began, thanks to which most of the collections can be accessed through terminals installed in the reading room.
The Casón building was built by Alonso Carbonela in 1637 as the ballroom of the Palacio del Buen Retiro. The interior was decorated by the Neapolitan painter Luca Giordano, who painted an allegory of the Golden Fleece on the vault of the building. It used to be a collection of 19th-century paintings. For some time you could also admire Picasso's famous "Guernica". Works by Arthur Douglas Cooper and Pilar Juncos were also exhibited here.