When my parents went on holiday to the Isle of Man, they sent me back a postcard of this famous Manx landmark. I decided it would make an interesting subject for raytracing. I got quite a long way along, but then started to get stymied by the fact that I only had one view of the wheel and there were details in it I couldn't see clearly enough to render properly. I could have persisted, inventing the details I couldn't see, but in the end I put the project on hold and left it languishing on my hard disc. Here is an older image and older PoV source code (shift- or control-click if you want to save a local copy). Please note, I don't guarantee that source and image coincide - I haven't re-rendered it to check, and don't currently intend to. The latest copy is in an archived DOS partition file which I can't currently access, but it's a much better version than this early one. Click on the thumbnail for the full-sized image: