The “Je Sers” Chapel Boat: A Floating Church on the Seine at Conflans-Sainte-Honorine
Moored on the Seine at Conflans-Sainte-Honorine, about 12 miles (20 km) northwest of Paris, Je Sers is a Catholic chapel built inside a former coal barge. Often described as unique in France, this floating church has served the families of the river for ninety years, in a town known as the capital of French inland navigation, or batellerie.
For travelers who love places with a story, it is one of the most unusual sights in the Paris region, and a quiet, moving stop along the Seine.
What is the Je Sers chapel boat?
Je Sers, which means “I serve” in French, is a barge about 75 meters (roughly 245 feet) long. It was built in 1919 as a reinforced-concrete cargo barge designed to carry coal. In 1936 it was bought and converted by the Entraide Sociale Batelière, a charity for boatmen’s families, together with Abbé Bellanger, and turned into a chapel and welcome center for the boating community. It was blessed by the bishop of Versailles and dedicated to Saint Nicholas, a patron saint of sailors and boatmen.
The chapel is lit from above by a glass skylight, and the whole vessel has been protected as a historic monument since 2020.


Why Conflans-Sainte-Honorine?
The town sits at the confluence of the Seine and the Oise, a strategic meeting of two rivers that made it a busy inland port for centuries. Over time it became known as the capital of the batellerie, the world of barge families and river trade.
That heritage is still visible. The Musée de la Batellerie et des voies navigables tells the story of life on the water, historic boats are moored along the riverfront, including the tug Triton 25, and every June the Pardon national de la batellerie brings the river community together for a festival of boats, processions and ceremonies. Up in the old town, you will find half-timbered houses, the Gothic church of Saint-Maclou and the medieval Tour Montjoie, with views over the Seine.
A church that is also a place of welcome
Je Sers is more than a curiosity. It remains a place of prayer, with Mass celebrated several times a week, and a place of welcome. The boat also hosts La Pierre Blanche, an association that offers welcome, lodging and social support to people in need. For many visitors, that living purpose is what makes the boat so moving.











