Épernay is a commune in the Marne department of northern France, 130 km north-east of Paris on the mainline railway to Strasbourg. The town sits on the left bank of the Marne at the extremity of the Cubry valley which crosses it.

Marne is a department in the Grand Est region of France. It is named after the river Marne which flows through it. The prefecture (capital) of Marne is Châlons-en-Champagne. The subprefectures are Épernay, Reims, and Vitry-le-François. It had a population of 566,855 in 2019.