Pharos in the Nile Delta has been suggested by R. McQuillen as the location of Atlantis. It should be noted that the cities of Canopus and Herakleon in the same area were submerged, apparently due to liquefaction, following an earthquake between 731 and 743 BC. If something similar occurred to Atlantis situated at Pharos it might explain the shoals of mud reported by Plato and may even have been the reason for the erection of the famous lighthouse there, completed around 280 BC.
This lighthouse at Pharos took 20 years to build and is reported to have been as much as 450 feet in height, topped with a statue of Poseidon (or Zeus). It is claimed that there was also a furnace on top which, according to Robert Temple , suggested that some form of mirror reflected light out to sea. There is evidence from early writers that nocturnal sea travel was commonplace, so some system of beacons to assist this, would have been a natural development.
In a study of ancient lighthouses (pharology) by Ken Threthewey(a), he indicates that there were probably precursors to the Alexandrian edifice, but that there is no archaeological evidence to support this contention. One suggestion is that altars, temples and latterly Christian churches frequently situated at the end of promontories may have functioned initially as navigational aids, keeping in mind that early Mediterranean seafarers preferred coastal hugging to open sea travel. In fact, I would think it strange if such locations were not used for beacons.
>A book review by Terrance M.P. Duggan draws attention to the use of the word ‘pharos’ as far back as the Homer’s time, centuries before the Alexandrine structure was built(c). Duggan has also noted in an extensive study of ancient beacons(d) how “sailing at night was practiced in antiquity, first by the Phoenicians” and that “later, sailing at night is mentioned repeatedly by Homer in the Odyssey.” It must be obvious that such regular nocturnal travel could not have been achieved without the availability of some system of warning beacons.
Duggan also notes the use of false beacons such as in the story of “Palamedes’s father, the King of Naupilus or of Euboea, then lit a series of false beacons leading to the shipwreck off Euboea of much of the Achaean fleet returning from the Trojan War, using false maritime navigational beacons to serve as a wrecker’s device, and with the use of these false navigational beacons quite clearly indicating the presence at this date of considerable numbers of genuine navigational beacons along coastlines to provide an expected navigational guide for ships sailing through the night.“
What I found really interesting was another quote by Duggan of a passage from Al-Mas’udi, circa 947 AD – “At the point where the Mediterranean Sea joins the Atlantic Ocean there is a lighthouse of stone and copper (bronze), built by the giant Hercules (probably to be associated with the location of the Phoenician Temple of Melkart-Herakles on the North African side). It is covered with inscriptions and statues whose hand gestures proclaim to those coming from the Mediterranean who wish to enter the Atlantic Ocean, ‘There is no way beyond me’” This is a clear association of Heracles with a lighthouse and raises the question of whether this was a more widespread occurrence, which seems possible.
At the other end of the Mediterranean, the Colossus of Rhodes is also thought by some(g) have functioned as a lighthouse, but at the very least was a daytime navigational marker, Heracles was also worshipped on the island as the founder of its first settlement.
The Tower of Hercules is an ancient Roman lighthouse on a peninsula about 2.4 km (1.5 mi) from the centre of the town of A Coruña, Galicia, in north-western Spain.<
Massimo Rapisarda & Marcello Ranieri have now published a paper(f) pointing to possible land based navigational aids, most likely, Phoenician, at the Sicilian promontory of Capo Gallo.
Threthewey, a leading pharologist, published Ancient Lighthouses  in 2018. Furthermore, he has also published a series of eight lengthy papers on pharology on the academia.edu website(e) .
Another paper by Marco Vigano also investigates the subject of proto-lighthouses(b), furthermore a book review by Terrance M.P. Duggan draws attention to the use of the word ‘pharos’ as far back as the Homer’s time, centuries before the Alexandrine structure was built(c). Duggan has also written a paper on The Missing Navigational Markers(d).
A recent book, The Electric Mirror on the Pharos Lighthouse, edited by Larry Brian Radka, argues spiritedly for the use of electricity at Pharos!