From the time of Alfred the Great until beyond the end of the Middle Ages, bridges were vital to the rulers and people of England, but they were expensive and difficult to maintain. Who then was responsible for their upkeep? The answer to this question changes over the centuries, and the way in which it changes reveals much about law and power in medieval England. The development of law concerning the maintenance of bridges did not follow a straightforward line: legal ideas developed by the Anglo-Saxons, which had made the first age of bridge building possible, were rejected by the Normans, and royal lawyers of the thirteenth and fourteenth centuries had to find new solutions to the problem. The fate of famous bridges, especially London Bridge, shows the way in which the spiritual, historical and entrepreneurial imagination was pressed into service to find solutions; the fate of humbler bridges shows the urgency with which this problem was debated across the country. By concentrating on this aspect of practical governance and tracing it through the course of the Middle Ages, much is shown about the limitations of royal power and the creativity of the medieval legal mind. ALAN COOPER is Assistant Professor of History at Colgate University.