Mount Hakurei

Mount Hakurei; a once sacred mountain of absolute purity and divinity. Beautiful flowers skimmed the surface, from the earth to the mountain formation itself, a place where no demon dared to enter. This served as the battleground for the one of the most prominent battles of the InuYasha franchise.

Saint Hakushin, a once revered and great monk fell into despair upon attempting to reach Nirvana and became a living Buddha as he died. In his misery, Naraku approached him and tempted him to the darkness. Manipulating him in his vulnerable state, the monk agreed to help him, and with his new powers, was able to manifest an impenetrable barrier that could ward off demons. Naraku used Mount Hakurei as his new base of operations while he constructed a more powerful body. In the anime this is where the kon blade of the Naginata of kenkon was sealed away.

Destruction
After Kikyo convinced St. Hakushin to release the barrier, Naraku's miasma corrupted the mountain turning its vegetation from a rich state into a state in which it appeared as a barren wasteland. Afterwards, demons started to emerge from the caves that were unaffected by the barrier. Then after that, when battling InuYasha and Koga, with a single attack he destroyed the mountain of purity. Before the destruction, any demon who sought to approach Mt. Hakurei became very sick as shown by Shippo and Kirara. Not only demons could be affected but humans as well. For example, Miroku was affected by the barrier when he was walking alone with Sango on Mt. Hakurei. Because of his lecherous thoughts, the mountain not only emotionally prevented him from these thoughts, but they physically did too, no matter how many times he tried to touch Sango's rear end.

In Later Chapters
Later on in the story Naraku goes here to reabsorb Onigumo's heart, hoping to make sure Kikyo cannot purify the Shikon no Tama because of Onigumo's negative feelings. The mountain now takes the appearace of several vegitated spikes, which are the mountain's remains.