Built in 1924, the 12-story, double-wing Spring Arcade Building was designed by San Francisco architects with continental backgrounds. Kenneth MacDonald had trained in Paris at the Ecole des Beaux Arts, and internationally recognized structural engineer Maurice Couchot was French. Originally known as the “Mercantile Arcade Building,” the dominant features of the three-story base of the building are the beautiful terra cotta archway lunette, decorated with ornate Beaux Arts/Spanish Renaissance motifs, and the cavernous midblock arcade connecting Spring Street with Broadway. On the rooftop of both the Broadway and the Spring Towers still stand the landmark old KRKD radio towers.