The Great Wall 长城

简介：
长城是世界七大奇观之一，是中国古代用作军事防御的一项宏伟建筑。长城最早大约出现于公元前7-前5世纪。长城是世界上修建时间最长、工程量最大的军事性防御工程，已被联合国教科文组织列入世界文化遗产名录。
Introduction:
One of the Seven Wonders of the World, the Great Wall was a grand construction that was purposely built for military defense in ancient China. Constructed as early as seventh Century B.C to the fifth Century B.C., the Great Wall is the project of military defense with the longest construction time and the usage of the largest quantities. It is also featured in UNESCO's World Cultural Heritage List.