Listed as a Historic Monument since 2022, the Walde Lighthouse is unique in continental Europe due to its original structure on wrought iron piles. It materializes the boundary between the North Sea and the Channel. The association Environnement et Patrimoines du Calaisis offers a guided walk on the beach to retrace the history of the lighthouse, put into service in 1859. The course crosses the dune and then takes the beach at the edge of the wet sand (no difficulty for a walker). It is not accessible to people with reduced mobility. Sports or hiking shoes are enough. Provide a warm outfit because a strong wind is often present (the proximity of the sand yachting base of the Hemmes de Marck is not due to chance). The presence of a seal colony on the sandbar is not uncommon. Common sense measures to not disturb them apply without exception. Bring binoculars and a camera. NB: The tidal coefficient does not allow to bypass the inlet safely and to get to the foot of the lighthouse. The observation will be 200-300 m from the building. Return to the car park by the same path (a priori around 10:15). In case of unfavorable weather forecast, the EPAC reserves the right to postpone the exit to the next day Sunday 17/09 at 08:45 or to cancel it. Looking forward to meeting you!