Great Wall of China

A section of the Great Wall of China, in the Pa-ta-ling area of Shanxi province. The wall has been rebuilt many times. Constructed under the reign of the first emperor, Qin Shi Huangdi, the present structure is largely the work of the Ming emperors of 1368–1644.

The Great Wall of China, photographed here near Beijing (Peking), China, is built of stone for much of its length, where it lies in rocky, hilly terrain. However, in desert areas where stone was not easily available, the builders used compacted earth and adobe.

The Great Wall of China is so large that it can be seen from space – but not with the naked eye. It is only visible via satellite, through an ultra-modern device with excellent magnification and resolution. The myth about visibility from space arose from the fact that the wall is long enough to track across the terrain when looking down from an orbiting satellite.

The Great Wall of China. This section of the Great Wall, some 80 km/50 mi from Beijing, dates from the Ming Dynasty (14th–17th centuries).

Continuous defensive wall stretching from western Gansu to the Gulf of Liaodong (2,250 km/1,450 mi). It was once even longer. It was built under the Qin dynasty from 214 BC to prevent incursions by the Turkish and Mongol peoples and extended westwards by the Han dynasty. Some 8 m/25 ft high, it consists of a brick-faced wall of earth and stone, has a series of square watchtowers, and has been carefully restored. It is so large that it can be seen from space.