Chartres Cathedral, the cathedral church of Notre Dame (Our Lady) in the city of Chartres, in northwestern France, is one of the foremost examples of High Gothic architecture, and widely imitated for its innovations in architecture, sculpture, and stained glass. Chartres Cathedral is also well known for its more than 150 stained-glass windows, most of which are original, dating from about 1210 to about 1260. They cover a surface area of over 2000 sq m (21,500 sq ft).