Knaresborough, when I visited, had just had an Arts Festival. Dotted all around the town were these rather marvellous trompe l'oeil features, a project that originated as part of the Festival a few years ago but which has been futher developed by Renaissance Knaresborough. (Click on each to really appreciate them).
A secret tunnel at the railway station..
Doors and windows..
Even Mother Shipton herself!
Apparently the town is well suited to this, as many of the Georgian buildings have 'blind windows' - bricked up windows. There are various theories about these - maybe they were a way of avoiding window tax, or simply used to keep the symmetry of the buildings without the expense of glass.