Notre-Dame is a medieval Catholic cathedral known to be one of the finest examples of French Gothic architecture.
Notre-Dame was among the first buildings in the world to use the flying buttress (is an arched structure that extends from the upper portion of a wall to a pier of great mass, in order to convey to the ground the lateral forces that push a wall outwards).
Many small individually crafted statues were placed around the outside to serve as column supports and water spouts. Among these are the famous gargoyles and grotesque. The statues were originally colored as was most of the exterior. The paint has worn off. The cathedral was essentially complete by 1345.
Numerous architects worked on the site over the period of construction, which is evident from the differing styles at different heights of the west front and towers. Between 1210 and 1220, the fourth architect oversaw the construction of the level with the rose window ( in the Rayonnant style) and the great halls beneath the towers.