Marais Audomarois Towpath Walk (Saint-Omer)

The Marais Audomarois is a wetland of canals, reedbeds and market-garden plots near Saint-Omer in the Hauts-de-France region of northern France. The towpath walk starts from the Maison du Parc Naturel Régional des Caps et Marais d'Opale on Rue de la Forêt in Clairmarais, and runs as a loop of about 10 km that takes 3 to 4 hours. The terrain is completely flat, with no meaningful elevation gain, so the difficulty comes from distance rather than slope. By car the trailhead is about 5 km from Saint-Omer. Visitors without a car can take the TER from Calais to Saint-Omer in about 20 minutes and continue by taxi for roughly €8. No permit is required. The surface is mostly grassy towpath, packed earth and short stretches of country lane. Paths can be muddy and slippery after rain, so waterproof boots are useful outside the driest months. Shade is patchy, provided by willows and poplars along the canals, while open sections are exposed to sun and wind. Landmarks include the traditional flat-bottomed boats used on the waterways, small bridges, farmland with vegetable plots, and the reedbeds that shelter birdlife. The park information house near the start provides maps and seasonal advice. Natural turn-around points are the bridge crossings, which allow shorter loops. Mosquitoes and other biting insects can be numerous in summer, especially near still water. There are no refuge huts and drinking water is not available along the towpath, so walkers should bring their own water. Cafés and shops are found in Clairmarais and Saint-Omer before or after the walk.