A slight sidetrip for a variation that probably wouldn't support a thread of its own:

A lightship, in this case the Bürgermeister O'Swald. The stamp honors the memory of the crew that was lost October 27, 1936, when the ship was lost in a hurricane. If you want to check your favorite mapping site, she was stationed at 54° 01' North, 8° 13' East.
Here is her profile drawing from a 1913 marine engineering journal:

Manning a lightship would not be a fun task, because in addition to the lighthousekeeper's task of keeping the light lit, you also had to constantly verify your position. And your job counted most when the weather was the worst. All this was done in close proximity to the hazard that you were marking for other ships.
Back on topic, as this has been posted on another thread, it doesn't take up any space to show it here, too:

This is the same light shown earlier on the half pence QE2 stamp, one of two lighthouses in Sierra Leone. This lighthouse dates to 1849. Here is a photo:
