Shadow Isles

The Shadow Isles were a group of islands in the Circle Sea on Avalon. Surrounded by a ring of islets and reefs, they were renowned for their danger, with treacherous waters and dangerous creatures common occurrences there. Notably, Helm Island in the Shadow Isles was the location of the fabled Merlin's Helm. The First Doctor and Ian Chesterton sailed aboard the Merrow to the Shadow Isles in search of the helm. (PROSE: The Sorcerer's Apprentice)