Land of the Sea

From Narutopedia

The Land of the Sea (海の国, Umi no Kuni) is featured in episode 169. Orochimaru had a hideout here, and several of his forbidden experiments were conducted here as well. One of his subordinates continued the work after Orochimaru abandoned it, leading to attacks on the local ships. It is not a prosperous nation, and relies on Land of Water ninja for protection.