The defences of Lugo are the most complete and best preserved example of Roman military architecture in the Western Roman Empire. Criterion (iv): The Roman walls of Lugo are the finest surviving example of late Roman military fortifications. Pressures affecting the Roman Walls include the effects of the use of transport infrastructure, water and relative humidity but these are all minor and under control. AuthenticityThe authenticity of the Roman Walls of Lugo lies in the way that they have survived intact for eighteen centuries. All restoration and maintenance work on the Roman Walls is carried out in strict compliance with the directives of the Advance Integral Plan for the Conservation and Restoration of the Walls of Lugo.