As in the later works, the castle is given qualities of Celtic Otherworld (including its invisibility from the outside and seemingly changing locations), as the story's original Grail hero Perceval visits it only when invited and then cannot find it again despite searching for years.

As befits the castle of the Grail, Corbenic is a place of marvels, including, at various times, a maiden trapped in a magically boiling cauldron, a dragon, and a room where (depending on text) either an angelic knight or arrows assail any who try to spend the night there.

Corbenic has a town, and a bridge which Bromell la Pleche swears to defend against all comers for a year, for love of Pelles' daughter Elaine (Morte, Caxton XI–XII).

Corbenic's seaward gate is guarded by two lions, aided by either a dwarf (Morte, Caxton XVII) or a flaming hand (Lancelot-Grail).

Helaine Newstead and Roger Sherman Loomis have presented a convincing case for the origins of the name Corbenic in a myth concerning a type of Welsh cornucopia – to wit, the horn (of plenty) of Brân the Blessed, a magical, food-providing talisman.