Lagny-sur-Marne (English: Lagny on the Marne) is a commune in the eastern suburbs of Paris, France. It is located 26.1 km. (16.2 miles) from the center of Paris.
The commune of Lagny-sur-Marne is part of the Val de Bussy sector, one of the four sectors in the "new town" of Marne-la-Vallée.
Lagny-sur-Marne annexed the commune of Saint-Denis-du-Port
Inhabitants are called Latignaciens
As of the census of 1999, the town has a population of .
Lagny-sur-Marne is served by Lagny – Thorigny
station on the Transilien Paris – Est
suburban rail line. This station, although administratively located on the territory of the neighboring commune of Thorigny-sur-Marne
, lies immediately across the Marne River
from the town center of Lagny-sur-marne.
Lagny-sur-Marne is twinned with Alnwick