Écluse du Moulin-du-Comte, Navigation lock in Rennes, France

The Écluse du Moulin-du-Comte is a lock on the Vilaine River in Rennes that controls water flow between two different elevations. The structure features the typical components of such works: gates, chambers, and walls that guide vessels through level changes.

The lock was built between 1822 and 1842 during the canalization of the Vilaine to improve shipping. This project was crucial for developing the region's economy and connecting communities along the river.

The lock takes its name from the Moulin-du-Comte, the count's mill that once stood on this reach of the Vilaine. Its position on the river through Rennes tied it to the millers and boatmen working the waterway, and the lock chamber is still the point where the canal's level changes are read today.

The lock is located on Allée Louis Lucipia and remains freely accessible from the surrounding area. Plan your visit for regular working periods to ensure you can see the structure and the canal without disruption.

The lock sits beside the former Moulin du Comte, a mill whose name it carries; the mill and its weir once used the same reach of the Vilaine. Its position at the junction with the canalised river made it a reference point for boat traffic entering Rennes from the south.