The Ming Emperors, having overthrown the Mongols from the north, devoted large amounts of material and manpower to making sure that they (and the other semi-nomadic peoples to the north) could not return.

Their methods of Great Wall building fused all that was learned by the two previous dynasties. First, a center of trampled earth was created. Then, around the firm center was applied a shell of stone and bricks. The bricks that were created by the Ming are so strong that they compare well with the ones we use today.

Near Beijing, the Great Wall is constructed from quarried limestone blocks and fired bricks.

The strong Ming wall was built across some of the most dangerous terrains in China, including steep mountains, sometimes on 75 degree inclines! It has been said that every foot of the construction of this Great Wall cost one human life.

The Ming Dynasty Great Wall starts on the eastern end at ShanHai Pass, near QinHuangDao, in Hebei Province, next to Bohai Sea. It once spanned 9 provinces and 100 counties, but the final 500 kilometers of the Great Wall to the west have all but turned to rubble. Today, the western end of the Great Wall effectively ends at the historic site of JiaYuGuan Pass, in northwest GanSu Province, at the limit of the Gobi Desert and the oases of the Silk Road.

JiaYuGuan Pass was intended to greet travelers along the Silk Road. Although the Great Wall now ends at JiaYuGuan Pass, there are many watchtowers extending beyond there along the Silk Road.

In 1644, after two years of trying, the Manchus finally crossed the Great Wall by bribing an important general, Wu SanGui, to open the gates of ShanHai Pass and allow the Manchus into China. Legend has it that it took three days for the huge Manchu army to pass through the Great Wall.

So began the Qing dynasty. After the Manchu conquered China, the Great Wall was of less strategic value, mainly because the Manchu extended their political control far to the north of it, much further than any previous Chinese dynasty.

The last Great Wall of the Ming Dynasty was a military fortification of great strength. However, historians are sometimes dismissive of its net value. It was astonishingly expensive to build, maintain and garrison and the resources the Ming spent on the Great Wall could have been spent on other military capabilities. The fact remains that the Great Wall was of no help in preventing the fall of the Ming Dynasty.

However, only because the currently prevailing dynasty had weakened from within were invaders from the north able to advance and then conquer. Both the Mongols (Yuan Dynasty, 1271-1368) and the Manchurians (Qing Dynasty, 1644-1911) were able take power not because of a weakness in the Great Wall but because of a weakness in the government. They took advantage of disenchantment and rebellion and stepped into the void of power without an extended war.

WatchTowers and Wall Design

Along the Ming Great Wall of China there are many watchtowers, spaced from less than a kilometer to several kilometers or more apart.

These were partly used to transmit military messages. Fire and smoke were the most efficient means for communication - fire was used at night and smoke during the day. Straw and dung was used for this. In 1468, a series of regulations set specific meanings to these signals: a single shot and a single fire or smoke signal implied about 100 enemies, two signals warned of 500, three warned of over a 1000 and so on. In this way, a message could be transmitted over more than 500 km of the Great Wall within a few hours.

During the Ming Dynasty, two-storied watchtowers were built on the Great Wall in strategic places. The ground floor was used for living, and storing food and weapons, and the top floor was used as a high lookout platform and also for defense. Canons were installed in strategic places, sometimes in watchtowers but also along the wall.