Zoana (ゾアナ?) is (was) a country in the Slayers anime found in the peninsula which was once sealed within the mazoku barrier. The previous king of the country was Moros, whose daughter, Martina Zoana Mel Navratilova and her husband, Zangulus (whom she married at the end of Slayers NEXT) are currently the King and Queen.
It seems that the country is quite small, as in the beginning of Slayers NEXT it was completely destroyed with a single hit from Lina Inverse's Dragon Slave. Since that incident, the kingdom is in the constant state of reconstruction. The reason for Lina destroying the kingdom (which was not exactly her target) was that the then-princess Martina had captured Amelia Wil Tesla Saillune, the princess of Saillune in order to conquer Saillune with her naive father, a plan which eventually failed.
While we got no word of whether the reconstruction was ever completed during later anime seasons, after the events of Slayers NEXT Zoana has appeared on a few occasions on maps. One such event occurred during the first episode of Slayers TRY when Prince Philionel El Di Saillune was giving a speech in the harbor where ships of different kingdoms were leaving for the expedition of the world beyond the peninsula. During that scene, the name of Zoana could be seen on a globe depicting the map of the Slayers world.