Caleise, Celybe, Chelibe, Collybe, Seloude, Tibise
A forest near the Corbenic (Carbonek), the Grail Castle, that extended to the sea.
Galahad traversed it, following Perceval’s sister to Goothe Castle, during the Grail Quest and united with Perceval and Bors at the ocean.
Found in the Vulgate Queste del Saint Graal, the name is given to the sea itself by Malory.
Sources
Vulgate Queste del Saint Graal | 1215-1230
Prose Tristan | 1230-1240
Le Morte Darthur | Sir Thomas Malory, 1469-1470