The Mutianyu Great Wall, located in Huairou District, is one of the best sections of the Ming Dynasty Great Wall. Its architectural design, such as the Central Gate Tower composed of three enemy-monitoring towers, Giant Corner Tower, double-sided crenels, and drainage channel of the horseway, is unique in the Great Wall. The three-dimensional effect of the Mutianyu Great Wall and the coexistence of internal and external branches also reflect the highest artistic achievement of the Great Wall construction in the Ming Dynasty.