AISNE, department, northern France, west of Ardennes (q.v.). Area 2,866sq.m. Pop. (1931) 489,368. It touches the western end of the Ardennes (93oft.) in the north-east, but its surface is all of secondary or tertiary rocks. The outlying masses of the latter, often with steep flanks, form important sites such as that of Laon, the capital, and the famous Chemin des Dames. The .Aisne enters the department from the east just as it leaves the chalk scarp and flows west to the Oise, the other river of the department. It has been made to stretch down to include the deep Château-Thierry portion of the Marne valley, too far west to focus on Epernay or Reims and allied to the hill country farther north rather than to Paris on the west. The department was the scene of much of the World War. It had a number of forests, but it lacks metallic ores, though quarries yield building stone, gypsum and clay. Mostly in the belt of rainfall boo-800mm., and well watered and sheltered, it has had great farming prosperity, with specialization in dairying towards the north-east. Of the towns, Guise in the north does agricultural other engineering and St. Quentin and numerous villages do weaving of cotton, wool and silk. St. Gobain has made mirrors since the 17th century. Sugar has been an important crop and in dustry. Communications are good by rail and by navigable rivers (Aisne, Oise, Marne). St. Quentin, Vervins, Laon and Soissons give their names to arrondissements and are, with Château Thierry and Hirson (q.v.), the chief towns. This department and that of Oise were rich in architectural monuments several of which are now ruined, but the churches at Laon, Braine and Urcel (mainly 12th century) have survived the devastation and the splendid Basilique of S. Quentin has been largely repaired, while the castle-ruin (14o0) of La Ferte-Milon has not suffered. Sois sons is the seat of a bishop in the province of Reims, the court of appeal is that of Amiens (Somme), which is also the centre of the end Army Corps. The department belongs to the educa tional province (academie) of Douai.