Here are some excellent free documentaries on YouTube you can mine for adventure material...
Monty Python's Terry Jones on the Crusades (he has a whole series of Medieval docs, I think this is the only one on YouTube, but there's a bunch more on Netflix if you have that)
(And if you don't want to listen to Terry Jones going on about the Middle Ages then, really, what kind of human being are you?)
BBC doc on Medieval maps, including lots of stuff about dog-headed men and a guy who uses his single grotesquely-swollen foot as a form of sunblock.
Leonard Nimoy narrating a thing on the Library at Alexandria...