High Quality Content by WIKIPEDIA articles! A separation barrier is a wall or fence 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 nomadic powers to the north; the most prominent recent example was the Berlin Wall that separated the enclave of West Berlin from the rest of East Germany during most of the Cold War era.