Beijing Travel Guide: Beijing Attractons: Great WallDespite the common assumption, the Great Wall can not be seen from the moon; it can, however, be viewed from astronauts in passing orbiters. It was also not built all at one, ti was built from the 5th to 16th centuries to be completed as a barrier against nomadic invaders from the north. The wall's origins date back at least to the 5th century b.c., when the rival kingdoms of the Warring States Period (453-221 b.c.) built defensive ramparts against their enemies. The First Emperor of unified China, Qin Shi Huang Di, fortified the barriers in the 3rd century b.c. Over a 10-year period, 300,000 conscripted laborers, many of them slaves, knit the walls into a continuous rampart to protect the western frontier. New sections extended the wall east to the Yellow Sea.
The Great Wall was constantly repositioned along new routes as successive dynasties rose and fell. In the year a.d. 607, more than a million workers toiled on this line of defense, but soon after the Great Wall was abandoned. The Mongols eventually broke through from the north and established the Yuan Dynasty (a.d. 1271-1368), making Beijing their capital. Their successors, the emperors of the Ming Dynasty (a.d. 1368-1644), set in motion the last great phase of wall building, which created the Great Wall as we see it today north of Beijing.
Its eastern foot rests in the Gulf of Bohai on the edge of the Yellow (or Eastern) Sea, its western 5,000km (3,333 miles) on the verges of the desert region.
Visitors to Beijing can visit the Wall at three locations: Bakaling, 80km north; and Simatai, 110km northeast. Built during the Ming Dynasty, the Badaling section is 7.8 meters high and 5.8 meters wide. While the ridge can be accessed on foot, the steep ascent is not for everyone and a cable car ride can be substituted. Another restored sector, at Mutianyu, can also be explored by foot up its long, steep stairs and restful terraces or by a recently installed cable car. Both sides are often crowded, which has been left in its ruined state. However, while visitors to the two restored areas can go by tour bus, those traveling to Simatai must have their own guide and means of transprotation.