Great Wall of China Construction

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The Great Wall as we know it is a structure made of bricks and stones. It has forts and passes, watchtowers and beacon towers. All very well organised to create a complete defence system.

However, the construction materials used across the entirety of the Wall depended on the location’s climate, i.e. desert to the west, mountains to the east, and what was locally available to quarry. The main materials used were: earth, reeds, sand, wood, stones and bricks. 

Workers would begin a section by building the towers first. They were made of wood and sun-dried mud bricks with sloping walls for stability. The rooftops were lookout and signalling stations. If enemies were spotted, fire was ignited in rooftop pits signalling the next tower to call for troops. Each tower then built a fire, becoming one long emergency call for assistance.

Outposts were built next on the enemy side of the Wall. These were forts occupied by garrisons who formed the first line of defence. They met the enemy first, before the rest of the Chinese armies arrived. 

When the towers and outposts were complete, the workers built the connecting walls by first erecting a bamboo frame. Dirt was dug out from nearby and dropped into the frame, the workers would then ram the dirt until compact. The dirt was added in layers until it reached the top of the frame. When finished, the frame was moved down the line and the process started again. 

Rubble was used to line the wall, stone lined the top and the road was paved. Battlements 6ft (1.8m) high had crenels and loopholes. Three storey watchtowers were built for surveillance and one to two storey beacon towers were for communications. Fortresses held the command posts and their gatehouses served as passes. 

Where possible, they used mountains and rivers as natural barriers, saving labour and costs and on steep mountain slopes they only built a single thin wall.

These basic principles of building were used all the way through the Ming era. With material and technological advancement, the Ming just made the Wall bigger and better by covering the walls with bricks and stone and used sticky rice to strengthen and waterproof their mortar mix. Making it more attractive was the added bonus.

Fast Facts:

Average height: 20-23ft (6-7m)

Average width: 13-16ft (4-5m)

Highest elevation: 4,722ft (1,439m) 

Lowest elevation: just above sea level