This free-standing chapel, the pantheon of Francisco de los Cobos, secretary to Emperor Charles V and his chief advisor in matters of the imperial funds, is a masterpiece by Diego de Siloé; its layout embodies the full funerary symbolism of the rotunda as an evocation of the Holy Sepulchre. Siloé's design was executed by Andrés de Vandelvira, who crafted the entire Sacristy. The result is a church that stands comparison with the finest Italian Renaissance architecture.