Dating from 14th century, these medieval passages under Exeter High Street are a unique ancient monument: no similar system of passages can be explored by the public elsewhere in Britain. Their purpose was simple: to bring clean drinking water from natural springs in fields lying outside the walled city, through lead pipes into the heart of the city. The pipes sometimes sprang leaks and repairs to buried pipes could only be carried out by digging them up as we do today. To avoid this disruption the passages were vaulted and it is down some of these vaulted passageways that visitors are guided.