Headcanon #1
Lighthouse were built as a monument to the Athenide.
Perse was often seen holding a lantern when guiding the dead of the sea to the underworld. The lantern was a gift from Apollo a little bit of his sun's light trapped in glass that would let you see in the darkest part of the oceans water. The sailors souls would see the light and instinctively move towards it knowing it was safety.
Perse's light was see as a symbol of safety and comfort. When a new temple was being built the priest decided to added a light to the top of the temple as a tribute to the Athenide Psychopompa. Sailor's would use the light from the temple to dodge the rocks not far from shore.
Soon lights where added on top of all the Athenide's temples as tribute. In later times becoming what is now known as Lighthouses.
