The term separation barrier is a euphemism for walls or fences constructed to limit the movement of people across a certain line or border, or to separate two populations. These structures vary in placement with regard to international borders and topography. The most famous example of a separation barrier is probably the Great Wall of China, a series of barriers separating the Empire of China from Mongolia and Manchuria; the most prominent recent example was the Berlin Wall that separated the exclave of West Berlin from the rest of East Germany during most of the Cold War era.
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