Mount Osore (恐山 Osore-zan) is a region in the center of remote Shimokita Peninsula of Aomori Prefecture, Japan.
According to popular mythology, Mount Osore (literally "Mount Fear") marks the entrance to Hell, with a small brook running to the neighboring Lake Usorisan that is equated to the Sanzu River, a river that deceased souls needed to cross of their way to the afterlife. The reputation is not surprising, given that the very volcanically-active site is a charred landscape of blasted rock filled with bubbling pits of unearthly hues and noxious fumes.
The Bodai temple (菩提寺 Bodai-ji) presides over it all and organizes the area's main event, the twice-yearly Itako Taisai festival. The grand festival is held over a period of five days beginning on July 20. In a ritual called kuchiyose (口寄せ), blind mediums known as itako claim to summon the souls of the dead and deliver messages in their voices.