History of the Great Wall of China the three, China's chief concern since the earliest times had been Mongolia – the home of many of the country's fiercest enemies including the Xiongnu, the Xianbei, the Khitans, and the Mongols. The Gobi Desert, which accounts for two-thirds of Mongolia's area, divided the main northern and southern grazing lands and pushed the pastoral nomads to the fringes of the steppe. On the southern side (Inner Mongolia), this pressure brought the nomads into contact with China. For the most part, barring intermittent passes and valleys (the major one being the corridor through Zhangjiakou and the Juyong Pass), the North China
Wildlife of China go a month or longer without drinking water. A thirsty Bactrian camel can drink 135 liters (30 gallons) in only 13 minutes. They can withstand extremely hot and cold weather and have broad hooves that do not sink in desert. Bactrian camels are known as the "boats of desert" – for millennia, they were used to carry goods along the Silk Road. Wild camels are critically endangered and found in the Gobi and Taklamakan Deserts. The wild boar, from which the farm-raised pigs was domesticated some 8,000 years ago in China, remains common in the Chinese wilderness. On occasion, boars