The Great Wall of China is located in northern China, stretching across several provinces. This historical structure was built and reconstructed over centuries, primarily from the 7th century BC to the 16th century during the Ming Dynasty, to protect Chinese states from invasions and raids. The Great Wall spans approximately 13,170 miles (21,196 kilometers) and features various materials, including stone, brick, tamped earth, and wood. It is one of the most significant symbols of Chinese cultural heritage, attracting millions of tourists annually and standing as a testament to the strength and determination of the Chinese civilization.