Lighthouse In Waves

Lighthouses near to each other that are similar in shape are often painted in a unique pattern so they can easily be recognized during daylight. This marking is called a daymark. The black and white barber pole spiral pattern of Cape Hatteras Lighthouse is one example. Race Rocks Light in western Canada is painted in horizontal black and white bands to stand out against the horizon.
Range lights
Aligning two fixed points on land provides a navigator with a line of position called a range in the USA and a transit in Britain. Ranges can be used to precisely align a vessel within a narrow channel such as in a river. With landmarks of a range illuminated with a set of fixed lighthouses, nighttime navigation is possible.