When it comes to border control, China wrote the book. Some time around 221 BC, Qin Shi Huang conquered several states along China’s border with Inner Mongolia. To get his newly minted Qin Dynasty off to a good start and to keep it safe from intruders, he ordered a wall built around it. It took years and cost tens of thousands, if not millions of lives, but that was a sacrifice he was willing to make.
Subsequent dynasties, mainly the Ming (in the 14th century) repaired and extended the wall some 5,500 miles making it officially Great. The portion seen in this photograph is at Gubeiko (the old north mouth) near Beijing and crosses Coiling Dragon Mountain and Crouching Tiger Mountain.
Photograph by Alan Tsai.