R(ich) McQuillen is an American investigator who has cogently argued for an Egyptian location for Atlantis. He has diligently gathered an impressive array of evidence from classical writers including Hellanicus, Solinus and Aeschylus to support his view and arranged the morass that is Greek mythology to construct a credible timeframe for the Atlantis narrative.
McQuillen places the Pillars of Heracles at Canopus, which was formerly in the Western Nile delta but is now submerged about 6.5km from the coast in the Bay of Aboukir. He is also of the opinion that the Egyptians used lunar ‘years’ rather than solar years bringing the backdrop to the Atlantis story into the 2nd millennium BC. McQuillen locates Atlantis at Pharos, which was near modern Alexandria. His website(a) is well worth a visit.
Extensive underwater excavations have been undertaken in recent years by Franck Goddio and his team with remarkable results(b).
It is also worth noting that the late Ulf Richter reasoned that a river delta was the most likely topographical setting for Atlantis.