Cantre'r Gwaelod
Cantre'r Gwaelod, also known as Cantref Gwaelod or Cantref y Gwaelod, is a legendary ancient sunken kingdom said to have occupied a tract of fertile land lying between Ramsey Island and Bardsey Island in what is now Cardigan Bay to the west of... Wikipedia
Characters: Gwyddno Garanhir; Seithenyn; Elffin ap Gwyddno