Senlis (săNlēsˈ) [key], town (1990 pop. 15,226), Oise dept., N central France, on the Nonette River. Wood products and mechanical and electrical equipment are the chief manufactures. Senlis has some of the best preserved monuments in France, including walls and towers from Gallo-Roman times and medieval ramparts and bastions. The Church of Notre Dame (12th–13th cent.) is one of the early masterpieces of Gothic architecture. Senlis also has a 15th-century town hall and the ruins of a château once inhabited by the first kings of France.