www.tourisme-saintomer.com. If you are heading back to the coast with time to spare, Saint-Omer makes a pleasant break about an hour from the ferry ports. The town is an ancient cross-roads between Flanders and Artois, with a bustling Saturday market held on central place du Maréchal Foch, in front of the Hôtel de Ville. A couple of narrow pedestrianized streets lead off the main square towards the 13th-16thC basilica: one street has a smart line in boutiques and food stores, the other tends towards café-restaurants and lawn mower repair shops.

Take a turn around the outside of the Gothic Basilique de Notre-Dame with its full complement of moss-tipped flying buttresses and hundreds of carved heads decorating the east end. The interior also has its share of statuary, and blue-green glass casts a submarine glow around the ambulatory. The Chapelle de Notre-Dame is stuffed-with heart-shaped votive offerings.

On rue Carnot, the 17thC Musée-Hôtel Sandelin displays fine arts, porcelain and furniture, plus the 12thC Pied de Croix de Bertin, a finely-wrought gold and enamel church treasure.

Stretch your legs amongst the topiary in the Jardin Public; or you can take to the watergangs, a network of little canals carved through the Audomarois marsh. Boats can be hired from points along route de Clair-marais (the D209, east of the railway station).