Modest Mussorgsky - A Night on the Bare Mountain
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The 20 scariest pieces of classical music

4. Modest Mussorgsky - A Night on the Bare Mountain
Beginning life as a tone poem called St. John's Night on the bare Mountain, Mussorgsky's most famous work was made more famous when it was revised by Rimsky-Korsakov, and then included in the soundtrack from Disney's Fantasia. Whatever incarnation it's in, it's a frightening masterpiece.