Jiayu Pass Fortress, China

Further into the desert and at the narrowest point of the Hexi Corridor is Jiayu Pass, the first fortress at the western end of the Ming Wall. Together with Shanhai Pass near the sea and Juyong Pass near Badaling, they are the most important passes along the Great Wall.

Construction on Jiayu began in 1372 AD by General Feng Sheng, at the onset of the Ming Dynasty. It was completed 168 years later in 1540AD. The trapezoid-shaped fort has a perimeter of 2,405ft (733m) and a height of 36ft (11m). It is a complete defensive system consisting of an inner and outer city, beacon towers, corner turrets, watchtowers, barbicans and pass gates. In front of the fortress is a spring that forms an oasis, which was one of the reasons for building here.

Being in the desert, the structure of the fort is different to the brick and stone walls in the far east. The desert soil, known as loess, is rich in calcium carbonate and when  mixed with water has self-cementing properties. To build the wall, the soil was tamped together in 5.5in (14cm) layers and between each layer was a spread of dried reeds that provided a drainage mechanism for the rain. This combination and the method of building made the walls tremendously strong.

South of the fortress is the ruin of the Great Wall’s first western beacon tower. When it was first built in 1539 AD, it stood 46ft (14m) high but now it is a pile of dirt, less than half the height. Although not much is left of this important outpost, it remains a marker of the Ming Wall’s western beginning. 

There is a legend told of an official in charge of building the fort asking the designer how many bricks would be needed for the construction. The designer promptly answered 99,999. When the official queried if that was enough, the designer added one more brick. When the fort was finished, there was one brick left over, which was placed loosely on one of the gates where it remains today.

About 5mi (8km) north of Jiayu Pass is the Overhanging Great Wall, a 750m long, fully restored wall, snaking up the hillside to a beacon tower. When it was built in 1540 AD, the wall was twice as long. Reminiscent of the various zig-zagging sections north of Beijing, the glaring difference is the terrain. Where in the east the landscape was verdant and much steeper, here in the desert it is barren and desolate. Even the earthy-coloured stairs leading up the mountain blend into the environment.