In the Italian La Tavola Ritonda, a castle owned by Uther Pendragon and Arthur. Tavola opens with a tournament, held by Uther, at the castle.
Guinevere holed herself up in the castle when Mordred usurped Arthur’s throne. Arthur, returning from his attack on Lancelot in Benoic (Benwick), engaged Mordred at the castle.
During the battle, Yvain (Ywaine) was slain and Arthur received his mortal wound – an event that traditionally occurs at Camlann. In response to a summons from Guinevere, Lancelot came from France and killed Mordred in front of the castle.
Source
La Tavola Ritonda | 1325–1350