This is a plan of Bodiam Castle in East Sussex. Marg drew it for me using a couple of existing plans I found on the web for reference. Having a drawing of it is handy, as it can be scanned at a high resolution and printed out (on several sheets of paper) at a scale for using with miniatures.
It is drawn on an A5 sheet of paper with a 7mm grid. Pads of the very same paper, along with larger A4 ones are available via my Kickstarter project.