Columbia subject headings:
Madrid (Spain)--Buildings, structures, etc.
Plazas--Spain--Madrid--History.
Public architecture--Spain--Madrid.
Puerta del Sol (Madrid, Spain : Plaza)--History.
Harvard subject headings:
Princeton subject headings:
Madrid (Spain)--Buildings, structures, etc.
Plazas--Spain--Madrid--History.
Public architecture--Spain--Madrid.
Puerta del Sol (Madrid, Spain : Plaza)--History.