Book excerpt: Britain is a treasure trove of medieval architecture. Almost every village and town in the land has a church that was built during the period, whose history is legible – to those who know how to look – in every arch, capital, roof vault, and detail of window tracery. By learning how to identify the stylistic phases that resulted from shifts in architectural fashion, it is possible to date each part of a church to within a decade or two; this book introduces all the key features of each succeeding style, from Anglo-Saxon and Norman through to the three great gothic styles, Early English, Decorated and Perpendicular. It will be indispensable to anyone who enjoys exploring medieval churches, and who wants to understand and appreciate their beauty more deeply.