Ever since the 13th century, clay roof tiles have added a tapestry of rich colours, shapes and shades to both the rural and urban built environment. Clay roof tiles have played a significant role in the historical development of architecture. The Romans were the first to make and use fired clay tile roofing in this country, and museum collections now bear witness to the widespread employment of this material. In the medieval period, the revival of the craft took place first along the eastern seaboard, where contacts with the continent were strongest and provided a strong, fire-proof alternative to thatching. In 1212AD, King John issued building by-laws for London to eliminate combustible roof coverings and replace them with tiles. Since that time, clay has been a highly sought-after material. History is embodied in every tile. In the 13th century, the price for roof tiles averaged at three shillings per thousand. Plain clay tiles are still based on dimensions standardised by Edward IV in 1477 AD and Tyler or Tiler is still a common British surname. By the 18th century, tiles had become the standard roof covering wherever there was an abundant local supply of suitable raw materials, a source of fuel and a thriving craft tradition. The production of clay tiles began as a very small scale industry, with many districts having only one source of supply. Over time, roofers developed their own construction detailing and distinctive methods of laying roofs that provided their neighbourhoods with a distinctive local appearance and an indigenous form of building. The process of industrialisation and the improvements to the national transportation network in the 19th century led to a widespread use of machine made, through still distinctive, clay roof claddings. Clay roof tiles are a beautiful and understated legacy from the past that continue to echo generations of craftsmen's skills in fashioning rich and colourful roofscapes out of common clay. Generations to come will still be able to enjoy the aesthetic beauty of clay - on their homes, schools, offices, hospitals, churches and public buildings. Now, in the 21st century, the quality of the built environment is becoming increasingly important and planners are keen to preserve the heritage and regional variation that remains. A panoramic look across the rooftops of Britain shows a patchwork of colours, with each region set apart from the rest by its own, distinct clay roof tile heritage.