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Under particular conditions, dry sand can produce surprisingly loud sounds when people walk, slide, or disturb it.
The phenomenon is associated with characteristics such as grain size, shape, cleanliness, and dryness. Different beaches can produce squeaks, whistles, or deeper booming sounds.
Famous examples occur in several deserts and coastal areas around the world.
A beach can therefore have a natural sound produced almost entirely by grains of sand moving against one another.
© Smithsonian Magazine