As I was reading the The Histories in an excellent "Ladmark Herodotus" edition, I stumbled upon the passage in 2.149, talking about Lake Moeris:
This is clearly a man-made lake which has been excavated, for roughly at its center stand two pyramids, each of them rising 50 fathoms above the surface of the water and extending just as far underwater. On top of each sits a giant stone statue on a throne.
No note or comment is provided by the editors for this - rather astonishing - claim, in an otherwise extensively annotated edition. I looked into the appendix that deals with the accuracy of Herodotus' account of Egypt, and, while it mentions the incorrect theory of the Lake Moeris being man-made, it doesn't say anything about the pyramids.
What is especially intriguing to me is that Lake Moeris is one of the places which Herodotus claims to have seen with his own eyes, and his account of the nearby Labyrynth and the lake itself is geenrally believed to be accurate.
I didn't find anything in Wikipedia, and general googling seems to mostly produce results from conspiracy theories sites, ancient aliens believers etc.
I was wondering if there was any serious attempt to locate the pyramids or refute the claim.
Despite having read and re-read Herodotus many times, it never occurred to me to check the veracity of this particular claim! So I took a quick look at the commentary by Alan B. Lloyd, who does an excellent job with the Egyptian material, and he notes here that two large statues of Amenemhet III (each at a height of roughly 40 ft., plus 21 ft. with the pedestal) did in fact stand near the lake, as documented by travelers before the eighteenth century of our era. Only the pedestals have survived intact to the present, unfortunately, though according to the old commentary by W. W. How and J. Wells, the Ashmolean Museum at Oxford has a nose from one of the statues.
Lloyd goes on to observe that "H.'s dimensions for the pedestals are grossly inflated," but he repeats the explanation offered by J. Ball in his 1939 book Contributions to the Geography of Egypt:
Ball explains the error neatly by pointing out that H. thought that the maximum depth of the lake was 300 ft. (c. 91.4 m.) (II, 149, 2). If, therefore, he were told that the pedestal was half-submerged, he would assume that 300 ft. lay below the water-level and 300 ft. above (Ball, Contributions, p. 207).
H.'s datum that the waters of L. Moeris rose half-way up the pedestal is invaluable for fixing the lake-level in his time. Since the pedestals are c. 18 m. above sea-level and c. 6.3 m. high, the level for part of the year must have lain approximately on the 20 m. contour (Ball, op. cit., p. 206).
I am no expert on this topic, of course. Perhaps someone else can provide some more details. :)
Sources: Allan B. Lloyd, Herodotus Book II, Commentary 99-182 (Leiden: E. J. Brill, 1993), 126; W. W. How and J. Wells, A Commentary on Herodotus, vol. 1 (Oxford: Clarendon Press, 1913), 242.
The "submerged pyramids" Herodotus saw were just the pedestals of two colossal statues of Amenemhet III.
Like many Greek and Roman tourists after him, Herodotus went to see the famous "Labyrinth" - actually the (now vanished) mortuary temple connected with the (still extant) Pyramid of Amenemhet III at Hawara. From the environs of the Labyrinth, Herodotus would have seen two tall statues in the distance. These colossal likenesses of Amenemhet III were actually located on the shore about ten miles away. But thanks to their high pedestals (which can still be seen near the village of Biahmu) and the shimmer of the Egyptian sun on the surface of Lake Moeris, they seemed to stand in the middle of the water. Herodotus must have asked his guides about the statues; and they, without actually bringing him anywhere near them, simply told the Greek tourist a tall tale about submerged pyramids, which he duly recorded in the Histories.
W. How & J. Wells, A Commentary on Herodotus, 264-5
M. Lehner, The Complete Pyramids, pp. 181-3
Today this is thought to be at Biahmu. This was long considered a problematic claim, and there once was a lot of argument about where "Lake Moeris" might have been, or indeed whether it existed at all. The first modern attempts to identify the specific location date back to Napoleon's expedition to Egypt in 1793. If you look at older literature, you'll find a lot of speculation on the subject, as this lake is discussed not only by Herodotus, but also by other ancient writers:
There has probably been no point in Herodotus' History where his veracity has been so seriously impugned as his account of the Lake of Moeris. This famous lake in Egypt in what is now the Faiyum mudiriyah, was mentioned not only by Herodotus, but by Strabo, Diodorus Siculus and Pliny the Elder; in antiquity, Herodotus' account was accepted with only minor alterations. It was never doubted that the lake existed. Modern geographers have been less willing to accept Herodotus at his word.
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Herodotus' account has been subject to correction on a number of points, and in fact there are geographers who suggest that his lake did not exist at all.
More recently, scholarly opinion following John Ball [1939] has settled on a plausible explanation, that the "Lake" was actually a temporary feature of a complex irrigation system affecting water levels in the Fayum "oasis".
The Fayum is usually called an oasis, but unlike the real oases in the western desert, which are irrigated by the underground Nubian aquifer, the Fayum receives its water supply exclusively from the Bahr Yusuf, a side branch of the Nile which leaves the river in the area of Assiut and enters the Fayum at the Lahun Gap.
{snip}
The Pharaohs of the Twelfth Dynasty, in particular Amenemhet III (who was still venerated as a god in the Ptolemaic and Roman periods) managed to stabilise the level of the lake at between 17 and 20 m above sea level, while the first Ptolemies took more radical steps to make the lake shrink down to approx. 45 m below sea level which more or less equals the measure of today.
{snip}
When Herodotus saw the two monuments of Amenemhet III at Biahmu and described them as standing in the middle of the lake, he was obviously visiting there when the lake was at its peak after the flooding.
Sources
Herodotus and the Problem of the "Lake of Moeris" [1965]
Recent Work on the Problem of Lake Moeris [1929]
Ball, John, Contribution to the Geography of Egypt, Cairo [1939]
