Procedure to Identify the Technological and Constructive Values in Historical Lighthouses: Application to the Lighthouses of Spain

This paper analyzes the heritage values of lighthouses related to science, technology, and construction in the age they were built and launched throughout history. The implementation of a lighthouse requires the resolution of several technological and constructive problems of great complexity. Since the beginning of the 19th century, the construction of lighthouses represented an emerging international market once the scientific advances were transferred to the industry. Spain has a geostrategic advantage by possessing approximately 6,000 km of coastline, necessitating an extensive network of lighthouses for maritime navigational aid. An in-depth analysis of the 191 active lighthouses has been conducted, concluding that 130 of them have some particular historical value. These lighthouses represent a clear example of Industrial Heritage because they are authentic signaling factories that possess active technology within the building complex. The paper aims to establish a procedure to identify the heritage values of historical lighthouses. This article describes the technology implemented initially and proposes a typological classification of the architectural composition identified in Spanish lighthouses. It is the first work conducted in Spain of this scope and nature, constituting an initial attempt to establish a listing of the historic lighthouses of Spain.