Just across the border from where I live there is this old watermill called the Haarmühle. It was built in 1619 on the spot of an older mill from 1331. Well worth a visit if you are in the neighbourhood of Alstätte, Germany, near the Dutch border.
Olympus XZ-1, 35mm, ISO100, f8, 1/2s
The mill is still operational, but only started up occasionally for tourists. It is picturesque from all angles, I will be going back to get some more pictures when the light is better.
Here's a picture of the gear box inside this watermill (repost):
Olympus XZ-1, 28mm, ISO100, f1.8, 1/8
It's all wood, and almost all connections are mortise-and-tenon. Some very nice old engineering there.