great wall of china
The Great Wall of China (Chinese: 萬里長城; pinyin: Wanli Changcheng) is the collective name of a series of fortification systems generally built across the historical northern borders of China to protect and consolidate territories of Chinese states and empires against various nomadic groups of the steppe and their polities. Several walls were being built from as early as the 7th century BC by ancient Chinese states; they were later joined together by Qin Shi Huang , the first Emperor of China.