land based cone maritime navigation signal light and marker guiding to safe passage through strait of trangsund to harbor of

aid aiding background baltic bay beacon buoy coast coastal cone day district equipment finland gulf harbor harbour isthmus karelian landscape leningrad light marine maritime mark marker mushroom nature nautical navigate navigation oblast peredovik port russia sea shape ship shipment shipping shore sky strait taper trangsund transportation trongzund uuras vessel vyborg vyborgsky vysotsk