The Great Wall From Space: Mostly a Myth

Despite the popular myth, the Great Wall of China is generally not easy to see with the unaided eye from low Earth orbit. It is narrow and blends into the landscape. NASA notes that astronauts find it difficult or impossible to distinguish without a telephoto lens, though it can be recorded in photographs. So the careful version is: the Wall can sometimes be captured in images, but that does not mean it is conspicuous to the naked eye from orbit.