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Maiden's Peak (Japanese: 乙女ヶ崎 Maiden's Cape) is a haunted location in Kanto. Ash and his friends visited it in the episode The Ghost of Maiden's Peak.
2000 years ago, a war was taking place and soldiers were being shipped overseas from Kanto to the battlefield. A maiden was in love with one of the soldiers who was being sent to war. She swore to wait on the cliff until her love returned, but he never did. According to legend, she died while standing there, and her body became part of the cliff itself.
Her petrified body became a monument, and the location was named for the legend. Her spirit still haunts the area with the help of a clever, talking Gastly.
In present times, a festival is held there at the end of the summer. Visitors honor the statue of the maiden, and at the end of the festival, people will release small boats with paper lanterns into the water. These boats are meant to help spirits find their way home, in hopes that the spirit of the maiden's lover will one day be returned to her.
Pokémon seen near Maiden's Peak