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
History of the Great Wall of China brought back the first reports of the Wall to the West, European scholars were puzzled that Marco Polo had not mentioned the presumably perennial "Great Wall" in his "Travels". Some 17th-century scholars reasoned that the Wall must have been built in the Ming dynasty, after Marco Polo's departure. This view was soon replaced by another that argued, against Polo's own account, that the Venetian merchant had come to China from the south and so did not come into contact with the Wall. Thus, Father Martino Martini's mistaken claim that the Wall had "lasted right up to the present time without