The Kingdom of Termina is the area where Link ventures off to in The Legend of Zelda: Majora's Mask and The Legend of Zelda: Majora's Mask 3D. Despite being singificantly far away, Termina shares many of the same traits and races as Hyrule. Instead of Hyrule Castle, the focus of the kingdom is the central Clock Town, where many of the Hylian inhabitants live.
Oddly enough, high above Termina is a small, angry, scary Moon.
Termina's Great Bay appears as a stage in Super Smash Bros. Melee.