The site where the Palace of the Cortes now stands was previously occupied by the Convent of the Holy Spirit, belonging to the Congregation of the Minor Clerics Regular, which was severely damaged by a fire in 1823.

With the advent of the liberal regime in 1834, the moderate government of Francisco Martínez de la Rosa decided to hold parliamentary sessions temporarily in the church of the convent.

The extension was built on an adjacent block where the Hospital of the Italians had stood between 1598 and 1885, and it was connected to the original structure via a bridge over Floridablanca Street.

The winning design was by María Rubert de Ventós, Josep Parcerisa, and Oriol Clos, who finalized the project together with Mariano Bayón and Justo F.

As a grand entrance, he designed a large portico with six Corinthian columns, supporting a triangular pediment adorned with a bas-relief depicting Spain with the Constitution, flanked by allegorical figures representing Strength, Justice, Liberty, Valor, Science, Harmony, Fine Arts, Agriculture, Commerce, Rivers, Abundance, and Peace.

[8] In 2012, the History Channel proposed funding the restoration of the missing part, but the request was ultimately denied for historical preservation and safety reasons.

On either side, two large paintings depict historic moments: Above the presidium, four sculpted figures represent the Navy, Agriculture, Commerce, and Science, created by Sabino Medina.

Its walls display twelve paintings representing Spain’s historic kingdoms, major cities, and rivers (Ebro, Tajo, Duero, and Guadalquivir), created by Vicente Camarón.