What was the closest in length to the great wall of china?

The Great Wall of China stretches approximately 13,171 miles (21,196 kilometers) in total length, including all its branches and sections built over various dynasties. The longest wall in the world that could be considered somewhat comparable in length is the "Green Wall" or "Great Green Wall" initiative in Africa, aimed at combating desertification, which spans about 8,000 kilometers (approximately 4,970 miles). However, no structure or wall approaches the Great Wall of China's length.