The present investigation examines the role of museum buildings in their consideration as heritage institutions. A particular interest in rehabilitation processes and conversion of international exhibition pavilions into museums will be assessed. The Archaeological Museum of Seville will be taken as a case study. The Ibero-American Exhibition of Seville (1929) was a paramount event in the city, with a vast development of the southern area of the city as well as a display of flourishing regionalist architecture. Its powerful image has transcended from this temporary event, embracing relevant institutions over decades, such as the Archeological Museum. Plus, historical preservation has enhanced its heritage value. Within the grounds of the historic María Luisa Park, the museum has undergone a remarkable evolution as an institution that requires a new relationship with its building, together with an adequation to new museological perspectives. During the lifetime of the museum, the former exhibition pavilion has experienced a succession of rehabilitation processes in the 20th century, always searching for a continuity with the concept of the original building. However, the evolution of the institution faces new challenges for the 21st century: display of the collection, technological issues, public and community services, network affiliation, etc. A series of cultural heritage protection measures that affect the property and its collections, its immediate environment, and the urban environment in which it is located, condition the building and its urban context. Nowadays, a new architectural intervention is in process, with the main goal of putting together all these requirements. The project also deals with the production of a new architecture of representation, respecting and rehabilitating the original regionalist building but also creating a contemporary image for the institution. The relevance of the museum, together with its urban role, make the Archeological Museum of Seville an important agent of cultural requalification. In conclusion, this paper will show how urban culture has been renewed, experiencing a decisive transformation of public spaces and cultural facilities, for leisure, education, or tourism. A new reconsideration of the Cultural Property in question is an experience that can be extrapolated to other museum experiences that emerged in the 20th century and that are currently undergoing a comprehensive reexamination.