The Pillars of the Earth (Kingsbridge, #1)

by Ken Follett

But all the while a question nagged at me: Why were these churches built? There are simple answers—for the glory of God, the vanity of bishops, and so on—but those were not enough for me. The building of the medieval cathedrals is an astonishing European phenomenon. The builders had no power tools, they did not understand the mathematics of structural engineering, and they were poor: the richest of princes did not live as well as, say, a prisoner in a modern jail. Yet they put up the most beautiful buildings that have ever existed, and they built them so well that they are still here, hundreds of years later, for us to study and marvel at.