Yes, ancient Egyptian monuments, and the pyramids of the Giza plateau in particular, were well known and often visited during from the Ptolemaic period onwards - and, of course, the Giza complex was one of the Seven Wonders of the ancient world in the list created by Antipater of Sidon.

We know something about the ways in which the pyramids were understood through visitors' accounts and also graffiti left on the monuments by these early "tourists".

Among early accounts ,the best known are probably those of Herodotus (about 430 B.C.), in chapter 124 of his Histories, Diodorus Siculus (about 60 B.C.), and Strabo (24 B.C.). Herodotus says:

The pharaoh Cheops made all the Egyptians work for him. . . . One hundred thousand men at a time worked for three months. Ten years of this forced labor were consumed merely in making the causeway along which the stones were hauled, which work, I consider, was hardly less than building the pyramid; for it is . . . all made of stones dressed [trimmed] and carved with images. Ten years, they say, were taken by this work and the making of underground chambers for the king’s burial in the hill on which the pyramids stand, which he turned into an island by cutting a canal from the Nile. The pyramid itself took twenty years to build: it is square, each face being eight hundred feet wide, and the height the same, and made of dressed stones most exactly laid, none measuring less than thirty feet.

The pyramid was built after the manner of steps, which some call “ramparts” and others “altar-steps.” When this first stage of construction had been completed, the remaining stones were raised by means of contrivances of short logs of wood. . . . The highest part was the first to be finished, and then the part next below it, and last they finished the lowest part that rests on the ground.

There are inscriptions in Egyptian characters on the pyramid telling how much was spent on radishes and onions and garlic for the workmen, and if I remember rightly what the interpreter told me when he read me the inscriptions, they cost a thousand and six hundred talents of silver. Now, if that is so, how much must have been spent on the iron used for the work and on food and clothing for the workmen? For I have said how long a time was taken by the building, and I am sure the hewing of the stones and the haulage and the digging of the underground works took no little time.

Diodorus's account, in chapter 63 of his Library of History, comments:

The eighth king, Chemmis of Memphis, ruled fifty years and constructed the largest of the three pyramids, which are numbered among the seven wonders of the world. These pyramids, which are situated on the side of Egypt which is towards Libya, are one hundred and twenty stades from Memphis and forty-five from the Nile, and by the immensity of their structures and the skill shown in their execution they fill the beholder with wonder and astonishment. 4 For the largest is in the form of a square and has a base length on each side of seven plethra and a height of over six plethra; it also gradually tapers to the top, where each side is six cubits long.

The entire construction is of hard stone, which is difficult to work but lasts for ever; for though no fewer than a thousand years have elapsed, as they say, to our lifetime, or, as some writers have it, more than three thousand four hundred, the stones remain to this day still preserving their original position and the entire structure undecayed. It is said that the stone was conveyed over a great distance from Arabia and that the construction was effected by means of mounds, since cranes had not yet been invented at that time; and the most remarkable thing in the account is that, though the constructions were on such a great scale and the country round about them consists of nothing but sand, not a trace remains either of any mound or of the dressing of the stones, so that they do not have the appearance of being the slow handiwork of men but look like a sudden creation, as though they had been made by some god and set down bodily in the surrounding sand.

Certain Egyptians would make a marvel out of these things, saying that, inasmuch as the mounds were built of salt and saltpetre, when the river was let in it melted them down and completely effaced them without the intervention of man's hand. However, there is not a word of truth in this, but the entire material for the mounds, raised as they were by the labour of many hands, was returned by the same means to the place from which it came; for three hundred and sixty thousand men, as they say, were employed on the undertaking, and the whole structure was scarcely completed in twenty years.

And Strabo's, in his Geography, Book XVII, is:

On proceeding forty stadia from the city, one comes to a kind of mountain-brow; on it are numerous pyramids, the tombs of kings, of which three are noteworthy; and two of these are even numbered among the Seven Wonders of the World, for they are a stadium in height, are quadrangular in shape, and their height is a little greater than the length of each of the sides; and one of them is only a little larger than the other. High up, approximately midway between the sides, it has a movable stone, and when this is raised up there is a sloping passage to the vault. Now these pyramids are near one another and on the same level; but farther on, at a greater height of the hill, is the third, which is much smaller than the two, though constructed at much greater expense; for from the foundations almost to the middle it is made of black stone, the stone from which mortars are made, being brought from a great distance, for it is brought from the mountains of Aethiopia; and because of its being hard and difficult to work into shape it rendered the undertaking very expensive. It is called "Tomb of the Courtesan," having been built by her lovers — the courtesan whom Sappho the Melic poetess calls Doricha, the beloved of Sappho's brother Charaxus, who was engaged in transporting Lesbian wine to Naucratis for sale, but others give her the name Rhodopis. They tell the fabulous story that, when she was bathing, an eagle snatched one of her sandals from her maid and carried it to Memphis; and while the king was administering justice in the open air, the eagle, when it arrived above his head, flung the sandal into his lap; and the king, stirred both by the beautiful shape of the sandal and by the strangeness of the occurrence, sent men in all directions into the country in quest of the woman who wore the sandal; and when she was found in the city of Naucratis, she was brought up to Memphis, became the wife of the king, and when she died was honoured with the above-mentioned tomb.

One of the marvellous things I saw at the pyramids should not be omitted: there are heaps of stone-chips lying in front of the pyramids; and among these are found chips that are like lentils in both form and size; and under some of the heaps lie winnowings, as it were, as of half-peeled grains. They say that what was left of the food of the workmen has petrified; and this is not improbable. Indeed, in my home-country, in a plain, there is a long hill which is full of lentil-shaped pebbles of porous stone;180 and the pebbles both of the seas and of the rivers present about the same puzzling question; but while these latter find an explanation in the motion caused by the current of water, the speculation in that other case is more puzzling. It has been stated elsewhere that in the neighbourhood of the quarry of the stones from which the pyramids are built, which is in sight of the pyramids, on the far side of the river in Arabia, there is a very rocky mountain which is called "Trojan," and that there are caves at the foot of it, and a village near both these and the river which is called Troy, being an ancient settlement of the captive Trojans who accompanied Menelaüs but stayed there.