Terebinthia

Terebinthia is a sovereign island-kingdom in the Great Eastern Ocean, the closest island to it being the island of Galma, which is a duchy under the authority of the Kingdom of Narnia. During the voyages of Caspian X a sickness on the island prevented them from going ashore there. It's name originates from the terebinth tree in the Bible. The imaginary country of Terabithia from the book "Bridge to Terabithia" is (though subconsciously) derived from the name of this island.