A major hurdle is proposing a plausible method of transmission whereby knowledge of a given site can be retained and communicated through the centuries. How would Plato have known the details of whatever archaeological remains you’ve dug up? In his dialogues, Plato claims that his knowledge of Atlantis derives from Solon, who got it in turn from the Egyptians. If we take this at face value, we would need to prove a relationship between Egypt and the unnamed site prior to the age of Solon (638-538 BCE) and Egyptian knowledge of the site’s layout, politics, internal organization, and destruction. We would also need to prove how and where Solon’s information was retained and communicated for roughly three centuries between him and Plato. Needless to say, there is not a single scrap of evidence—no statue, no vase painting, no inscription, no papyrus fragment, no wall painting—nothing that indicates Egyptian or Greek knowledge of anything like Atlantis prior to 360 BCE.
Contrast this with an actual documented instance of historical memory. In the Iliad (c. 800 BCE), Homer records the story of Troy, long believed to have been a legendary city as mythical as Atlantis. But Homer included bits of genuine Bronze Age information, including references to a helmet made of boar’s tusks that was used only in Mycenaean Age (prior to 1200 BCE), which indicated a core of genuine history underneath layers of myth. The Greeks, however, lived among the ruins of the Mycenaean Age but knew so little of that time that they assumed the ruins were the work of Cyclopes and the men of that era demigods. These same people somehow retained street-level knowledge of Atlantis but not their own cities?
Homer’s geographic information led Heinrich Schliemann to a site in Turkey where he found a city that has been identified as the site of Troy. However, Homer’s information was not perfectly accurate, but rather highly distorted, the result of imperfect transmission across centuries, contaminated with error and more recent information.
But this is not all the ancient evidence. Homer was not alone in mentioning Troy—an entire series of myths and epics by many hands recorded parts of its story. We also have Bronze Age Hittite records recording interactions with Wilusa (another name for Ilion, or Troy). The Hittite records confirm that a ruler named Alexander once reigned in Troy, just as in Homer the son of Troy’s king is Alexander (also called Paris).
In this case, we have contemporary records, an archaeological site, and later Greek recollections of genuine Bronze Age material. These many strands work together to tell us that the site Schliemann found in Turkey is the place known as Troy. What do we have to support claims for Atlantis? We have Plato’s (fictional) dialogues, and nothing else. The Egyptians, who recorded interactions with ancient peoples ranging from the Minoans and the Mycenaeans to envoys from the Near East, are silent about Atlanteans. The Greeks included Atlantis in no myths, legends, or epics. Nearly every ancient city that was genuinely prominent in the Bronze Age has myths associated with it, even if that city ceased to exist in later ages, as Martin Nilsson explained in his classic The Mycenaean Origins of Greek Mythology almost a century ago. But somehow Atlantis got left out. Even the ancient authors themselves were fairly certain Plato made it all up.
In absence of any evidence outside of Plato for Greek knowledge of Atlantis, and in the absence of any plausible way for the Greeks (or even the Egyptians) to have known about the destruction of Atlantis, or proof that they did, we must conclude that Atlantis was what Plato meant it to be: a fictional double for Athens.