Marne (French pronunciation: [maʁn]) is a department in north-eastern France named after the river Marne (Matrona in Roman times) which flows through the department. The prefecture (capital) of Marne is Châlons-en-Champagne (formerly known as Châlons-sur-Marne). The subprefectures are Épernay, Reims, Sainte-Menehould, and Vitry-le-François.

The Champagne vineyards producing the world-famous sparkling wine are located within Marne.

Marne is one of the original 83 departments created during the French Revolution on March 4, 1790. It was created from the province of Champagne.

Marne has a long association with the French Army. The training ground of the Camp Militaire de Mailly straddles the border with the département of Aube in the south while that of the Camp de Mourmelon occupies a large area north of Châlons-en-Champagne. The smaller Camp de Moronvilliers lies to the east of Reims and the Camp Militaire de Suippes lies to the east of that. These are all on the chalk of the Champagne plateau, a feature comparable in geology but not size, with the British military training ground on Salisbury Plain.

Marne is part of the region of Grand Est and is surrounded by the departments of Ardennes, Meuse, Haute-Marne, Aube, Seine-et-Marne, and Aisne.

...
Wikipedia