The Domesday Book, freely available online for the first time. You can search by place, name or simply browse the book.
Project creator Anna Powell-Smith wrote for the Open Knowledge Foundation blog:
Domesday Book might be one of the most famous government datasets ever created. Which makes it all the stranger that it’s not freely available online – at the National Archives, you have to pay £2 per page to download copies of the text.
Domesday is pretty much unique. It records the ownership of almost every acre of land in England in 1066 and 1086 – a feat not repeated in modern times. It records almost every household. It records the industrial resources of an entire nation, from castles to mills to oxen.