This monograph compares the city walls of two famous historical cities in China and the West. It tries to reveal the process of the formation of the differences in the defensive walls between the two cities representing the classical Chinese and Western civilizations. The two authors are distinguished scholars from China and Italy with outstanding achievements in architectural history research and heritage protection. The book details research on the historical evolution of the defensive walls of the two cities as well as on their city walls, landscapes and urban texture, wall restoration, wall planning, and urban planning for city walls. It is an innovation for comparing cities, architecture, cultures, and heritages between China and the West. It serves as a window and a platform for Chinese and foreign readers to understand and communicate about Chinese and Western architectural history, urban planning, and heritage protection.