The medieval area of Laon was built on the top of a flat plateau. It has the largest number of historical buildings per square meter in France. Notre Dame is the third cathedral to be built on this site. Because it was safe high up on the plateau, many people wanted to live here, and the city had a lot of money. When the architecture of the previous cathedral went out of style, they simply tore it down and built this one in the early Gothic style around 1150. In 1854, the nave started to detach from the facade, so they had to detach all the stones, fill in support, and then reattach each stone. This is the only church in the region that wasn’t damaged by bombs in the World Wars. They’re hard to see in the photos, but there are 16 life-size oxen sculptures at the top of the towers, most likely because oxen were used to carry stone up the hill.
The rose windows are possible because the ends of the church are flat. While the church wasn’t damaged in the wars, there was at one point an explosion that blew out the windows, and the stained glass windows in the photos above were repaired. The rest of the windows along the walls were replaced with lighter stained glass, which is why the church is so bright inside. A unique feature of this cathedral is its four levels of elevation. Flying buttresses were mastered later, which allowed cathedrals built in that style to achieve great height with only three levels of elevation.