Great Wall of China the optics much better, rendering photographic evidence irrelevant to the issue of whether it is visible to the naked eye. Great Wall of China The Great Wall of China is a series of fortifications made of stone, brick, tamped earth, wood, and other materials, generally built along an east-to-west line across the historical northern borders of China to protect the Chinese states and empires against the raids and invasions of the various nomadic groups of the Eurasian Steppe with an eye to expansion. Several walls were being built as early as the 7th century BC; these, later joined together and
Great Wall of Qi Great Wall of Qi The Great Wall of Qi () is the oldest existing Great Wall in China. Construction of the wall started in 685 BC (during the Spring and Autumn period) by the state of Qi, to defend itself against an invasion by the Kingdom of Chu. The existing sections date back to 500 BC. Construction ended during the Warring States period. The wall stretches from the areas under the administration of the present-day city of Jinan to the present-day city of Qingdao across the territories of the present-day cities of Tai'an, Zibo, Laiwu, Weifang, Linyi, and Rizhao. Its