Countries in attendance of the exposition included: Portugal, the United States, Brazil, Uruguay, Mexico, Peru, Argentina, Chile, Colombia, Cuba, Venezuela, the Dominican Republic, Bolivia, Panama, El Salvador, Costa Rica, and Ecuador.

Primo de Rivera allowed the Spanish King Alfonso XIII to give the final words and officially open the exposition.

Not long before the opening of the Exposition, the Spanish government also began a modernization of the city in order to prepare for the expected crowds by erecting new hotels and widening the medieval streets to allow for the movement of automobiles.

The building contained documents, maps, and other objects related to Christopher Columbus' discovery of the Americas, including a set of 120 letters and manuscript that had belonged to him, the last testament of Hernán Cortés, and detailed dioramas of historic moments.

Other nations, including Bolivia, Panama, El Salvador, Costa Rica, and Ecuador displayed their native products in the Commercial galleries of the Americas (Spanish: Galerías comerciales americanas).

They have also been featured in a number of films, including Lawrence of Arabia, The Wind and the Lion, and Star Wars: Episode II – Attack of the Clones, among others.