The famous structure in China built to protect against invasions from northern tribes is the Great Wall of China. Construction began as early as the 7th century BC, with enhancements made under various dynasties, notably during the Ming Dynasty. The Wall was designed to safeguard against raids and invasions from nomadic groups, such as the Mongols. Its sheer scale—stretching thousands of miles—served not only as a military barrier but also as a means of controlling trade and immigration along the Silk Road. Today, the Great Wall stands as a UNESCO World Heritage site and symbolizes China's historical resilience and architectural ingenuity.