Rose Window

Compared to later cathedrals, Laon has fewer glass because it was an early Gothic cathedral.  Most of its glass is from the 13th century, but has been fixed to its original form in the 19th century.  The Laon cathedral has four rose windows which are: East, West, North, and South.  The East facade of the cathedral has a very large rose window, and is above the main alter.  The East's structure is identical to the West.  The North, which is located in the transept, is filled with medallions and the South is very interesting because of its structure.  

http://www.ookaboo.com/o/pictures/topic/80010/NotreDame_of_Laon

http://www.trekearth.com/gallery/Europe/France/North/Picardie/Laon/photo217575.htm