World longest wall

Over 2000 years ago Qin Shi Huangdi built a wall to protect his dynasty. It was no ordinary wall, it was up to 25 feet tall and 15 - 30 feet thick.

Oops, forgot to mention, it was about 5,000 km. long. You guessed it, Qin Shi Huangdi built the Great Wall of China.

Later dynasties added to the wall and currently, including branches, the Great Wall of China measures in at over 6,000 km.

Qin Shi Huangdi's Great Wall of China