Tour Saint-Louis, Historic tower in Port-Saint-Louis-du-Rhône, France

The Tour Saint-Louis is an 18th-century stone tower in Port-Saint-Louis-du-Rhône, in southern France, near the mouth of the Rhône river. The square limestone structure stands about 50 feet (15 meters) tall, has three floors, and a flat roof terrace that opens onto the surrounding landscape.

The tower was built in 1737, financed by a tax on salt passing through the Rhône imposed by a royal decree of 1723. It belonged to a line of river towers serving as guard posts, lighthouses and refuges. During the Revolution it was renamed Tour des Embouchures and sheltered an Arles revolutionary section. It was listed as a historic monument in 1942 and acquired by the municipality in 1973.

The first floor of the Tour Saint-Louis holds a collection of about 170 birds of the Camargue, arranged by habitat. The ground floor, by contrast, houses the town's tourist office, and the second floor is given over to temporary exhibitions.

The ground floor houses the town's tourist office, the starting point for information on the Rhône delta. The interior spiral staircase leads up to the turret and the fortified roof terrace. The building is a listed monument and the tower stands about 7 km from the present mouth of the Rhône.

The tower's designer was the military engineer Jacques Philippe Mareschal, and three local masons carried out the work. Its limestone came from Beaucaire and Fontvieille. Because the Rhône mouth kept shifting, the river was already several hundred metres from the tower by 1772 and lies about 7 km away today.