The oldest intact building in Saint-Maur-des-Fossés, this church is dedicated to Saint Nicolas, patron saint of school children, but also of mariners, many of whom disembarked at the port of the abbey, on the Marne. The building has been modified several times, which explains the different styles of construction. If the bell tower is Romanesque, typical of the twelfth century, the choir (of the thirteenth century) is Gothic, with an imposing canopy of nearly 8 meters in height! The church has been listed as a historical monument since 1947. Since the end of 2020, the city of Saint-Maur-des-Fossés, in partnership with the Heritage Foundation and the Île-de-France Region, has launched a major renovation program of the building: replacement of the coverage of the choir and the bell tower, restoration of the structure, renovation, replacement of many very damaged stones (including columns and capitals), cleaning of some stained glass windows, etc. Since the beginning of 2022, interior work has begun with the demolition of the plaster vault of the 1930s, the restoration of the early 13th century frame and the reconstruction of the Romanesque vault.