Jiayuguan Fort, Gansu Province 甘肃省，嘉峪关城
A close look at the map shows the strategic location of this fort. This is the end of the Great Wall of China, which I walked upon at the beginning of the trip. The fort is the last remaining outpost that protected Han China 汉族 from invaders.
It was also used as a jumping-off point for expelling criminals. They would bring criminals to the fort then set them westbound with no provisions. Just start walking.
Inside of the fort looking west.
Chinese past in the foreground, Chinese present in the distant background.
China today gives its people a blanket of smog from Beijing to Jiayuguan. These were taken in the early morning so you can still see a little blue sky. By the time I left (two and a half hours later) the sky was covered grey.