Not One Wall, but Many

The Great Wall is not a single continuous structure. It is a patchwork of walls, trenches, and natural barriers built by different dynasties over 2,000 years. Combined, all the sections stretch more than 21,000 km — enough to cross the United States roughly five times.

Most of what tourists see today is Ming Dynasty construction from the 1400s to the 1600s. Many earlier sections had already crumbled by the time the Ming began rebuilding.