yeah well, maybe between 1/3 and half of the tombs or remains of all important historic 'world leaders' or military men of influence who made the differences in the Etruscan, Roman, Greek, Persian, Seleucid, Babylonian, Akkadian, Sumerian, Hittite, etc. empires.
Also a pretty good deal of the great persons being mentioned in the Biblical and Hebrew traditions (some would argue the level of history in there, but still I don't argue the tradition as long as there are no counterfactual indications or clues to forgery of historical fact) are still unfound (or maybe destroyed). Think of Nehemiah, Aaron, Pontius Pilatus,... Pick one
Anyhow I'm getting pretty interested in the Biblical history part (even though it hosts probably a stock of very fragmentary, doubtful or conjectured chronology or simultaneities that just seem too funny to have coincided)... but that makes the challenge of looking for clues, right? As long as certain old scrolls remain locked or unaccessible, the mainstream scholars won't rest to find out.