1. Siege(s)

      The seats at the Round Table - had a magical property. The name of its proper occupant appeared in letters of gold on the back of each chair, seemingly whenever he was near enough to come in and take his seat. Nevertheless, when a knight was known dead, his successor was chosen by natural means - appointed by the King on the advice of counselors, or possibly elected. There must have been a waiting list of candidates.

      Ideally, companions of the Table should not fight each other, except "for love" or at tournaments. There are, however, numerous instances of Table knights killing their comrades in battle, frequently through the careless but common habit of fighting first, with a strange or a covered shield, and then of identifying yourself to your opponent, or checking to learn his identity after the damage has been done.

      There seems also to have been some rivalry, especially in the early days of Arthur's court, between the companions of the Round Table and an auxiliary company of Arthur's warriors known as the Queen's Knights.

      Also, of course, there was inevitable jealousy and friction between personalities. Lancelot and Gawaine themselves, for instance, were dear friends; but some of their respective followers were capable of vicious bloodshed in the argument of which of the two great knights was the greater.

      The Knights of the Round Table repeated their vows every Pentecost.

      See also
      Listed Knights at the Round Table | The Legend of King Arthur

    2. Siege Perilous
      Perilous Seat, Seat of Danger, le Siege Perilleus, Siege Perilleux

      A place at the Round Table, so named by Merlin, who said it was reserved for the holiest of knights, the one whould achieve the Grail. [More]

    3. Siege Redoutez
      le Siege Redoutes

      A seat at the Grail Table at which only Josephe, the son of Joseph of Arimathea, might sit.

See also
Seat | The Legend of King Arthur