if you want to learn more:

NOVA explores the building of the Gothic cathedral -- taller than the Egyptian pyramids, big enough to encase the Statue of Liberty, weighing as much as the Empire State Building, yet apparently constructed (entirely by hand) of nothing but light, colour & air.
Try your hand at making some faux medieval stained glass. Or check out the work of some of your predecessors, working on Chartres Cathedral ca. 1220.
Unravel (if you are so inclined) some of the math behind the construction of medieval cathedrals.

You can also discover how a medieval cathedral is like a 1953 Citroën.

 

Check out the Bayeux Tapestry, a near-contemporary record of William's conquest of England (apparently commissioned by his half-brother Odo) in 11thC comic-strip fashion
or get yourself a free screensaver of the whole Tapestry (actually an embroidery, but the name has stuck).

 

Read (some of) the versions of Urban II's sermon and decrees at Clermont, 1095, as well as some Bukhari Hadiths on Jihad.

You can visit the ongoing archaeological investigations at Vadum Iacob, an unfinished Crusader castle (in modern-day Israel) taken by storm in 1179 – the bones of humans, mules and an unfortunate pig speak eloquently of its demise.
or view the more substantial standing remains of several other Crusader fortresses, at Crac des Chevalliers and Shaizar (both in modern-day Syria), St Hilaron (Cyprus), Montréal (Shawbak) and Karak (both in modern-day Jordan).

Usamah attests to how dramatically the lives of some Europeans changed in the Levant: they were exposed to new foods (though they did not quite change to a Muslim diet), adopted new styles of dress (one council even went to the trouble of legislating an ethnic dress code), and in time actually came to feel that ‘[they] who were Occidentals ha[d] now become Orientals’, or so at least some of them claimed. (Are you willing to take Fulcher at his word? What might be the subtext of his statements?)

Collected snippets tell the bizarre story of the Fourth Crusade in 1204, which ended up not in Outremer but in Constantinople – and, instead of fighting Muslims, toppled a Christian government.

The Russian city of Novgorod, founded by vikings and (until the 15thC) a serious contender for primacy over Kiev and Moscow, is a treasurehouse of archaeological finds.