The Encyclopedia Americana (1920)/China, Great Wall of

CHINA, Great Wall of, the White Wall, the Wall of 10,000 Li, the largest artificial defense structure on the face of the earth, a barrier extending for about 1,500 miles in the north of China proper, of which it partly forms the boundary. Its western end is in the deserts of central Asia, its eastern reaches the sea to the northeast of Peking, and it has an extension to the Sungari River to the northeast. It was erected as a barrier against the inroads of the barbarous tribes, and part of it dates from about 214 B.C.. The greater part, however, was constructed during the latter half of the 14th century. It is carried over height and hollow, and avoids no inequality of the ground, reaching in one place the height of over 5,000 feet above the level of the sea. Earth, gravel, brick and stone were used in its construction, and in some places it is much more substantial than in others. Its greatest height, including the parapet on its top, is about 50 feet, and it is strengthened by towers at regular distances. The average height of the wall is about 22 feet and the width 20 feet. The towers are about 40 feet high. Consult Geil, ‘The Great Wall of China’ (London 1909).