Big Churches and Stained Glass

There are three defining characteristics of Gothic architecture: pointed arches, a ribbed vault, and flying buttresses. This allowed architects to give the church larger windows and much bigger which allowed for a much more spacious and bright, inviting cathedral. These churches express the power and wealth of the church in the middle ages. Many churches and cathedrals took a century or more to build. That takes commitment.

As time went on, mural paintings (which had been widely popular) began to loose favor to stained glass. Due to the new Gothic style of architecture, large stained glass windows could now be placed in cathedrals. Illustrated texts provided ideas for the designs of many of the windows. These windows were often separated into twelve pieces, supposedly representing the twelve apostles. Stained glass windows are still in use today and are normally one of the key markers that you are in a church should you get lost. That is, if the giant Jesus statue isn't enough.

http://www.historylink101.com/lessons/art_history_lessons/ma/index.htm