The pyramids of Giza still retained their outer casing into the middle ages, and only lost it when the Arabs started to use it as a source of stone. But in 1332 a German noble, Wilhelm von Boldensele, while on pilgrimage in the orient, visited the site. In his Itinerarius Guelielmi de Boldensele in terram sanctam  he writes:
Beyond Babylonia (Cairo) and the river of paradise, in the direction of the desert that lies between Egypt and Africa, there are several monuments of the ancients, shaped like pyramids; two of them are amazingly large and high, with very large, polished stones, and on these I found characters inscribed in different languages. In one monument I came across the following Latin verses, chiselled in stone:
Vidi pyramidas sine te, dulcissime frater,
Et tibi, quod potui, lacrimas hie moesta profudi,
Et nostri memorem luctus hanc sculpo querelam.
Sit nomen Decimi Cetianni pyramide alta
Pontificis comitisque tuis, Trajane, triumphis
Lustra sex intra censoris consulis esse.
I have seen the pyramids in stone without you, beloved brother,
and for you I have grieved here as much as I could, and shed my tears;
And mindful of our grief I chisel this lament:
May the high pyramid know the name of Decimus Cetiannus,
The pontifex and companion of your triumphs, O Trajan,
(Who within six lustra was both censor and consul??).
The inscription and the stone on which it was inscribed have long since vanished from the world. But the name of D. Cetiannus, priest and companion of the emperor Trajan is preserved; because a German traveller twelve centuries later happened to write down the graffito.
I wonder what remains of antiquity might be mouldering in Arabic texts, unknown because Arabic literature is pretty much unknown and inaccessible, untranslated because unknown?
- No modern edition seems to exist: I accessed a translation of extracts in J.P.A. Van der Vin, Travellers to Greece and Constantinople. Ancient Monuments and Old Traditions in Medieval Travellers’ Tales (PIHANS 49), 1980. [27 cm, softcover; X, 751 (2 vols.)]. ISBN: 90-6258-049-1. p.574 f, esp. p.577-8. Downloadable here.↩