This 'In a Nutshell' guide examines the history, functions and traditions associated with the most dominant architectural structure on city skylines - cathedrals. Located at the heart of cities, cathedrals have traditionally been a spiritual and communal touchstone at the centre of municipal life. This comprehensive overview makes use of examples of cathedrals from around the world to illustrate the evolution of different styles of cathedral, from the Roman basilica to the soaring gothic, and the religious significance of these changes.