Of course they did.
Herodotus told them in his History
Herodotus' description of the Giza pyramids are interesting, not least because clearly his Egyptian sources of info didn't know much of what they were talking about. The names associated with the three major pyramids there are mixed but correct (Cheops instead of Khufu, Khefren, and Mycerinus rather than Menkaure) if apparently assigned wrong.
It's apparent that his sources mangled Egyptian history, assigning the "heresy" of Akhenaten to the much earlier Cheops/Khufu, restoration of Tutankhamen (originally Tutankaten) to Mycerinus/Menkaure, and putting the 18th dynasty Akhenaten after the 19th dynasty Ramses II.
This conflation by the Egyptians may have been the result of the later 18th Dynasty's deep interest in the Giza monuments. Revival of the Aten deity took place at least as early as Amenhotep III, but his son really went gonzo with it.
OTOH, Herodotus gives the overall duration of Egypt as 3000 years from his own time, which is at least in the ballpark (by his time, the Giza pyramids were about 2000 years old), and gives the construction of the causeway as ten years and construction of the Great Pyramid as twenty, without saying exactly how long before his time it happened.
He discusses the early, prehistoric Nile in an interesting fashion:If then the stream of the Nile should turn aside into this Arabian gulf, what would hinder that gulf from being filled up with silt as the river continued to flow, at all events within a period of twenty thousand years? indeed for my part I am of opinion that it would be filled up even within ten thousand years. How, then, in all the time that has elapsed before I came into being should not a gulf be filled up even of much greater size than this by a river so great and so active?