Valley of the End

The is located close to the border of the Land of Fire and the Land of Sound. Shortly after the foundation of Konoha, the Senju's leader, Hashirama Senju became the First Hokage, much to the dismay of the fallen Uchiha leader, Madara Uchiha, who intended to destroy the village with the forced assistance of Kurama — the Nine-Tails. The valley was carved out by Hashirama's Top Transformed Buddha's barrage. The battle ended with Hashirama victorious, Madara escaping his death and going into hiding, and Kurama being sealed within Hashirama's wife, Mito Uzumaki.

The destructive power displayed in the epic battle left a scar in the earth that would come to be called the Valley of the End. With the waterfall serving as a border between the Land of Fire and the land that was later known as the Land of Sound, the valley was later memorialised with two giant statues of the main combatants: Hashirama on the Land of Fire's side of the waterfall and Madara on the opposite side to symbolise his defection from their village. The statues are posed to make the Traditional Shinobi Sparring's Seal of Confrontation, which is protocol before a duel.

Years later, at the end of Part I, Naruto Uzumaki chased the now missing-nin and also teammate, Sasuke Uchiha to the valley in order to bring him back to the village before the latter attempted to kill him to acquire the Mangekyō Sharingan. Ultimately, using their greatest attacks at the same time, the battle ended with Sasuke emerging as the victor (though he ends up with a broken arm and a scratched Forehead Protector), with the statues of Madara and Hashirama receiving moderate damage during the fight.

In Part II, Tobi goes to the valley and sits atop Madara's statue as he muses over what path Sasuke will take. Moments after the Fourth Shinobi World War, Naruto and Sasuke once again arrive to the valley for a rematch. Their destructive capability having been enhanced since that time, the two devastated the valley, leaving much of it destroyed by the end with Naruto as the victor (though both of their dominant arms were destroyed). Much of both statues were completely destroyed, leaving only the two hands, one from each statue, forming the Seal of Reconciliation, symbolising Naruto and Sasuke's reconciliation and having finally settled their differences as well as Madara and Hashirama having settled their differences beforehand and the war between Asura and Indra coming to an end.

Sometime after the battle between Naruto and Sasuke, Kido Tsumiki and Magire collected DNA samples left behind by the two combatants in the valley in order to produce their Tailed Beast Drug and a drug that can bestow the Sharingan.

Trivia

 * The valley was part of the background in the fifth, twelfth, and twentieth Naruto: Shippūden openings.
 * In the Studio Pierrot produced anime cutscenes of Naruto Shippūden: Ultimate Ninja Storm Generations, both the start and end of Hashirama and Madara's battle were greatly elaborated. During this depiction, it was shown that a single deflected Tailed Beast Ball from Kurama resulted in the formation of the Valley of the End.
 * In Tobi's "recollection" of the events, Madara was stabbed through the front. In Hashirama's retelling of the events, he had actually stabbed Madara from behind.
 * Originally, there were two rocks in the centre of the waterfall that separates the two statues. However, during Naruto and Sasuke's final battle, the two rocks are noticeably missing.
 * In various video game adaptations, barring liberties being taken with the valley's elements, the highest point of the waterfall is often the main battlefield/stage. The source material's waterfall base being playable is only added in later instalments, which so far, Naruto: The Broken Bond is the only video game that averts this during its release (though the first portion takes place on the Madara statue's head akin to the source material).
 * Another exception is the initial instalments of the Naruto: Ultimate Ninja Storm games, where the battle actually takes place on a high-rocky plateau far away from the waterfall itself (as opposed to being anywhere close to it). Pre-release demos had the battle being fought at the bottom of the river.