The famous barrier built in China is the Great Wall of China. This monumental structure was primarily constructed to protect against invasions and raids from nomadic tribes and has a history spanning over two millennia. The wall stretches across northern China and showcases various architectural styles and materials used over different dynasties. It was built using earth, wood, bricks, and stone, depending on the region and the time period. Today, the Great Wall stands as a UNESCO World Heritage Site and symbolizes China's strength, history, and effort in unifying its vast territories.