Christianity has its quirks, too.

When I first visited England, I would visit a cathedral, and read in the guidebook, "In the north aisle…" and I would wonder "How am I supposed to know which aisle is north? I didn't bring a compass!" Later I learned that cathedrals were always oriented with the altar at the east end. Why is that? Is that where we get the word "oriented"? How strict is/was the rule? Does the same rule apply to parish churches? In America, as far as I know, churches and cathedrals are built every which way. What about in other countries?