[5] The department borders Nord (to the north), Somme and Oise (to the west), Ardennes and Marne (east), and Seine-et-Marne (south-west) and Belgium (Province of Hainaut) (to the north-east).

The Scheldt (which takes its source near Le Catelet), the Aisne, the Marne, the Ourcq, the Vesle, the Somme (which rises in Fonsommes), the Oise, and the Serre.

In the south of the department, there is the Surmelin, the Verdonnelle, and the Dhuys (this river is channeled into the Dhuis Aqueduct, 131 km long, to supply drinking water to Paris since 1 October 1865 and also more recently the Leisure Park of Marne-la-Vallée).

Weather Data for Saint Quentin – Roupy The department is crossed by three railway lines from Paris: the first two from the Gare du Nord and the third from the Gare de l'Est: In 1873, the department of Aisne had 10 railway companies with a total length of 382 km.

As a place of residence for some families working in Paris or Île-de-France, Aisne was for many years a department rather oriented to the left, with a majority on the General Council on the left since 1998, and the same for the majority of parliamentary seats representing the department in the National Assembly.

[15] In the second round of the 2022 French presidential election, Aisne was the mainland departement with the highest percentage support for her.

Aisne lost some of its population in the second half of the 19th century, due to the rural exodus but this was limited by the industrial development in the north of the department (Saint-Quentin, Chaunois, Thiérache).

Greatly affected by the First World War, the department has seen its population grow slightly to the same level as in 1900.

Population development since 1791:The boat tours relates in part to the Canal de Saint-Quentin with its electric towage and two tunnels (Lesdins and Riqueval/Vendhuile).

[citation needed] The British Expeditionary Force (BEF) had initial early successes driving the Germans back to the Aisne River; the German troops dug in and managed to hold out against both British and French attacks.

This German entrenchment was to mould the entire face of World War One as both sides began digging in and fortifying their positions.

This linguistic variance probably explains the difficulty for residents south of Aisne to identify themselves as belonging to the Picardy region.