The round table at which Arthur's knights sat, with no head or foot so that none should have precedence and all were equal. It was said to have been a wedding gift from King Leodegrance of Cameliard upon Arthur's marriage to Leodegrance's daughter Guinevere.
It is unclear how many knights could be seated at the table, with numbers ranging from 12 to 150 or more. One seat was left empty however, the Siège Perilous or "Danger Seat," which no one could occupy safely except for the true Grail Knight.
The Round Table is first mentioned by Wace in his Roman de Brut (1155).
See also Knights of the Round Table.