Light House Boat

The boat in the background of this picture is a floating light house! I had never heard of this before, but we saw this one in Copenhagen. I have learned that the proper term is Lightvessel.

They were used to warn ships of danger in areas where it was not possible to build a lighthouse. There are some records that indicate that the Romans built ships with large fires for beacons. Modern lightvessels were first used in the 18th century.

They are no longer used. They have been replaced by light houses or automated light buoys.