#gallery  narrow recessed balcony area along an upper floor on the interior of a building; usually marked by a colonnade
  supertype:  #balcony  a platform projecting from the wall of a building and surrounded by a balustrade or railing or parapet
  subtype:  #amphitheater__amphitheatre  a sloping gallery with seats for spectators (as in an operating room or theater)
  subtype:  #choir_loft__choirloft  a gallery in a church occupied by the choir
  subtype:  #organ_loft__organloft  a gallery occupied by a church organ

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