This building provides 24/7 watch and surveillance services year-round. Like the 12 others installed along the Atlantic coast, the Chassiron signal tower primarily serves a watchdog role. French Navy lookouts constantly monitor ship movements in their assigned area and are connected to the Brest base to issue alerts in the event of difficulties. This rescue mission is complemented by more strictly military prerogatives.
The signal tower is steeped in history. It was put into operation at the beginning of the 19th century and, at 28 meters tall, is the elder of the famous Chassiron lighthouse, located a short distance away.
The Chassiron signal tower on the island of Oléron can be visited during the month of August. The Navy offers visitors the chance to explore this site, which is usually closed to the public, and learn about the work that goes into it. Please note that this tour is exceptional and highly regulated, as the site belongs to the French Navy, so it's out of the question to allow just anyone to board the semaphore lookout at any time.
Reservations are made at the tourist office, and two groups of 10 people are formed for tours, usually on Tuesdays.