Edifici Gas Natural, also known as Torre Mare Nostrum, is an office skyscraper located in the La Barceloneta neighbourhood of the Ciutat Vella district in Barcelona, in Catalonia, Spain.It is the headquarters building of the Spanish Gas Natural company.DescriptionThe Edifici Gas Natural building was designed by the architects Enric Miralles and Benedetta Tagliabue in the High-tech architectural style. It was completed in 2005, and officially inaugurated in 2008.It has 20 floors, and rises 86m. It has an innovative and distinctive image, because the building has two lower horizontal glazed blocks protruding and cantilevered out from the main tower.It is located near the seafront, and to the southwest of two other La Barceloneta skyscrapers, the Hotel Arts and the Torre Mapfre.