The Palace The Palau National is the most spectacular building in Spain Square. It was built for the Universal Exposition of 1929,with the intent to build a monumental building. The architects were Enric Català and Pedro Cendoya, with the collaboration of Pere Domènech i Roure. The palace has undergone some restorations by the Italian architect Gae Aulenti, and now houses the Catalonia National Art Museum (MNAC). PAINTINGS AND SCUPTURES YOU WILL SEE..