The Observatoire de Sainte-Cécile rises to 25 meters in height. It can be accessed via the Saint-Paul walkway, which is 32 meters long and spans a 15-meter ravine above Allée Pasteur to connect what was formerly called the hills of Saint-Paul and Sainte-Cécile. This monument has been very well preserved. It was built in 1863 by architect Paul Régnauld who was assisted by a young engineer named Gustave Eiffel. You may know of a certain work of his in Paris?
The tower has a single-person spiral staircase that takes you up to a small observation deck for great views over Arcachon and the Basin.