Lighthouses were built along shorelines around the world for the single purpose of guiding travelers through the often dangerous and rough waters.
Each lighthouse had its own unique structure. Each light signal identified the specific location for the travelers.
Many early lighthouses were lit with candles, oil lamps and, later, electricity. However, a better way to disperse the light in a wider, stronger beam was sorely needed. Around 1821, a young Frenchman by the name of Augustin Fresnel (pronounced “freh-nel”) invented a central lens surrounded by prisms, which dramatically increased the strength of the light source. Fresnel lenses were installed in lighthouses around the world, and still can be found in some lighthouses.