Kirigakure no Sato

Village Hidden in Mist

Kirigakure (?? Kirigakure no Sato?, literally "Village Hidden in Mist") is one of the five great hidden villages and is located in the Land of Water. Its leader is the Mizukage. Little is known about Kirigakure, except that its ninja specialize in water-based jutsu. However, it would also seem that many of its ninja wield swords, based on flashbacks in the anime. In the past, the graduation exam for becoming Genin was rather inhumane: students who had been friends, trained together, and ate from the same table, were pitted against one another in fights to the death. This gruesome method was cut short, however, when Zabuza Momochi, a boy who had failed to pass the preliminary exam to even attend the ninja academy, went mad and killed all of the students in that year's graduating class.
The seven greatest ninja in the village are known as the Seven Swordsmen of the Mist, and each one wields a large and/or unique weapon. Kisame Hoshigaki, Zabuza Momochi, and Raiga Kurosuki, the three known members of the group, all became missing-nin. Of those three, only Kisame is still alive.
This village was once the home of the famous Kaguya clan, who had a kekkei genkai ability allowing them to control their own bones. The Kaguya clan was wiped out after they went to war on their own village. The reason for the Kaguya's clan actions was their love for battle and killing. Presumably, the Land of Water was already at peace, which caused the clan to attack their ninja village for their love of battle. They were soundly defeated, leaving Kimimaro Kaguya as the only survivor.
In chapter 303, this country is briefly referenced by Yamato as "the Village Hidden in the Bloody Mist", a nickname it had gained through its practice of pitting trainees against one another in order to make them into emotionless killing machines. Yamato contends that Sai was subjected to this method in preparation for serving Danzo's Root division.