#fortress__fort  a fortified defensive structure
  supertype:  defensive_structure__defensivestructure__defense  a structure used for defense; "the artillery battered down the defenses"
  subtype:  alcazar  Alhambra  martello_tower  Tower_of_London
  part:  battlement__crenelation  a rampart built around the top of a castle with regular gaps for firing arrows or guns

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