earthen parts had begun to collapse—and extended it 300 miles (280 kilometers) across the Gobi Desert. Han builders corrected the problem of the sandy soil by reinforcing the compacted earth with willow reeds. They also built beacon towers at 15- to 30-mile (25- to 50-kilometer) intervals and used smoke signals to warn of attack. All trade routes passed through the Wall.

The final construction phase, which gave the Wall its present form, was undertaken early in the Ming dynasty (1368–1644). Having finally expelled the harassing Xiongnu and their Mongol rulers, the Ming emperors set about securing their empire. They repaired and enlarged the Wall, constructing extensions of tamped earth between kiln-fired brick facings across some of China’s most mountainous terrain. The Ming wall averaged 25 feet (7.6 meters) in height; it was 15 to 30 feet (4.5 to 9 meters) thick at the base, sloping to 12 feet (3.7 meters) at the top. The watchtowers were redesigned and cannon, bought from the Portuguese, were strategically deployed.

For all its size and splendor, the Great Wall seems to have been a functional failure, with little military value. Only when China was weakened internally were northern invaders—the Mongols (Yuan dynasty) in 1271 and the Manchurians (Qing dynasty) in 1644—able to seize power without engaging in an attenuated war. Since the seventeenth century parts of the Great Wall have been quarried for their brick or stone; others have simply crumbled, while those in marshy areas have been buried by silt. Two stretches—the Badaling and Mutianyu sections—north of Beijing have been reconstructed and opened as a tourist attraction. In 1979, the Chinese government declared it a National Monument, establishing a commission to oversee its preservation; in 1987 it was inscribed on UNESCO’s World Heritage List.

Further reading

Luo, Zewen, et al. 1981. The Great Wall. New York: McGraw-Hill.

Schwartz, Daniel. 1990. The Great Wall of China. London and New York: Thames and Hudson.

Waldron, Arthur. 1990. The Great Wall of China: From History to Myth. Cambridge, UK: Cambridge University Press.

Great Zimbabwe

Republic of Zimbabwe, Africa

The ruins of Great Zimbabwe (Bantu for “stone house”) stand about 17 miles (30 kilometers) southeast of the modern provincial capital, Masvingo, and east of the Kalahari Desert between the Zambezi and Limpopo Rivers. They cover about 200 acres (80 hectares). The largest of about 300 such sites in the region, Great Zimbabwe was once the greatest city in sub-Saharan Africa. Misguided and racist Victorians—and others since—thought Africans incapable of such sophistication, and they therefore incorrectly concluded that ancient Phoenicians, Romans, or Hebrews created the amazing structures. The British archeologists David Randall-MacIver (1905) and Gertrude Caton-Thompson (1929) carried out excavations and discovered that the place was indeed indigenous African in origin. Their conclusions were confirmed by further investigations made by R. Summers, K. R. Robinson, and A. Whitty in 1958. The builders were ancestors of the modern Shona people of Zimbabwe. Even in ruin, Great Zimbabwe has been called “remarkable,” “majestic,” “awe-inspiring,” and “timeless”; when intact, it was an architectural masterpiece. Now known as the Great Zimbabwe National Monument, the site was inscribed on UNESCO’s World Heritage List in 1986.

The area was first settled by Bantu-speaking farmers, perhaps in the second and third centuries a.d. A second phase of occupation began about a.d. 330. The grasslands in the foothills of the Mashonaland plateau provided excellent pasture, and between 500 and 1000 the cattle-herding Gokomere people overran and absorbed the earlier inhabitants. Rich local gold deposits were later utilized, and it seems that some stone walls were built toward the end of that period. Scholars remain divided on how the Mwenemutapa of Great Zimbabwe attained their high lifestyle and widespread influence. Some believe that it came from cattle wealth and coastal trade in gold (with contacts as far afield as India and China). Others suggest that a powerful politico-religious ideology “gave them a competitive edge over neighbors” so that they could coerce the human resources needed to build their city. But as yet there is no evidence that their success depended upon a single factor.