Building the Great Cathedrals [Les Cathédrales dévoilées]

These skyscrapers of stone dominated skylines for nearly a thousand years. Now, a team of scholars and builders investigates how they we went up, and why some of the tallest fell down. Embedded in stone and stained glass, they uncover a hidden mathematical code — ripped from pages of the Bible — that was used as a blueprint to build the great Gothic Cathedrals.