Notre-Dame de Paris, referred to simply as Notre-Dame, is a medieval Catholic cathedral on the Île de la Cité (an island in the Seine River), in the 4th arrondissement of Paris. The cathedral, dedicated to the Virgin Mary, is considered one of the finest examples of French Gothic architecture. Several of its attributes set it apart from the earlier Romanesque style, particularly its pioneering use of the rib vault and flying buttress, its enormous and colorful rose windows, and the naturalism and abundance of its sculptural decoration.

Source: Wikipedia