Corner Tower, Jingshan. Two postcards show the highest frequency of Red Mansion scenery. The corner building has a unique and colorful shape, a cross-shaped roof, three layers of double eaves, multi-angle staggered, and large wooden frame and bucket arch are very complex. Only after careful measurement and research by the relevant personnel, can we realize the wonderful law, which embodies the extraordinary wisdom of the working people in ancient China. At present, the northwest corner building of the Forbidden City has been renovated. Colour harmony, yellow glazed tile roof and gold-plated top shine in the sunshine, against the vast sky, more and more solemn and beautiful.