Walls have been built since ancient times, to mark borders, protect kingdoms and settlements, or keep out unwanted people. In more recent times, walls have also been built to serve as memorials and structures of art.
Here are 13 walls from around the world, ancient and modern, and famous for their history, cultural or political significance.
The Great Wall, China

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Walls of Ston, Croatia

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Hadrian's Wall, England

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Vietnam Veterans Memorial, Washington, D.C.

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Berlin Wall, Germany

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Sacsayhuamán, Peru

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Western Wall, Jerusalem

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Walls of Troy, Turkey

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Chewing Gum Wall, Seattle

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Great Zimbabwe Wall, Zimbabwe

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Walls of Babylon, Iraq

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Ancient walls of Istanbul, Turkey

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Israeli West Bank barrier wall

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