Noble, Tubele, Tubelle
A castle in a valley, seemingly some two days’ ride from the castle of King Amans’ daughter, which is near Cameliard.
During the Grail Quest Sir Bors, arrived here, learned of an impending tournament between the Earl of Plain (Count of the Plains) and the Lady of Hervin’s nephew, the Lady of Tubele. Sir Bors encountered and battled his brother Lionel at the castle.
Malory mentions this castle, he, however, does not give it a name, and Vulgate VI does – indeed, various manuscripts of the Vulgate give it various names.
Source
Vulgate Queste del Saint Graal | 1215-1230