Why are lightships sometimes used insted of lighhouses?

Answer 1

Lightships are used instead of lighthouses in areas where it is impractical to construct a permanent structure, such as in deep water, shifting sands, or in regions prone to severe weather. They can be relocated as needed to mark changing navigational hazards. Additionally, lightships can provide more flexibility and can be equipped with modern navigational aids, making them effective in marking important maritime routes.