This windmill is in York and has been restored in the past few years, but this is the first time I noticed the fan tail at the back. This allows the cap of the windmill to rotate by itself until it's in the right direction for the wind, meaning that someone doesn't have to pull the cap manually.
They are apparently most often found in England, Denmark and Germany, and didn't really make it to the rest of Europe. It's a shame because it saves a lot of effort! - Lucy
