Ault and its cliffs, south of the Baie de Somme

Picardy's coastline is not very extensive, but it boasts a truly surprising diversity of seascapes. While the beaches north of the Baie de Somme are characterised by sand and dunes, a completely different geography awaits walkers heading south.

The transition begins at the Pointe du Hourdel, which closes off the southern part of the Bay of the Somme, and continues all the way to the beach at Onival (Ault), via the seaside resort of Cayeux-sur-Mer: all along this stretch of coastline, an immense pebble beach borders the sea.

Constantly pushed back by the sea, but also piled up by human hands in the 18th century to form a natural dyke, this strip of pebbles forms a protective barrier to a large flat area of ancient mollières (salt marshes) in the Bay of the Somme. It is on these salt meadows that the region's famous AOC lambs are reared, as well as Hensons horses, a local breed.

The Hâble d'Ault wetland is emblematic of this molliere landscape, with its grassy meadows, marshes and farmland just before the first cliffs of Ault. With no relief, this protected natural area is a delight for birds (270 species) and, by extension, for budding ornithologists and hunters...

From the beach at Onival, in the seaside section of Ault where some pretty Belle Epoque residences still stand, the Picardy coastline rises and becomes more rugged. The chalk cliffs rise up to 38 metres above sea level. A foretaste of the famous Côte d'Albâtre, which begins (or ends) here, south of the Somme.

Tucked away between its cliffs, Ault is struggling to hide a certain decline: it is far from being the most fashionable resort on the Côte d'Albâtre. As you wander through the old-fashioned streets, you'll find an old-fashioned atmosphere that will appeal to the nostalgic.

Lovers of the great outdoors are in for a treat: as you leave Ault to the south, a path leads up to the green peaks of the limestone cliffs, whose whiteness reinforces a striking contrast of colours. The backdrop is the sky and sea, whose tones change according to the weather and tide times. A magnificent setting for a walk!

This pretty walk takes us to the next valley, the Bois-de-la-Cise, with its houses and old villas, its promenade, its wood and its pebble beach.

From Le Bois-de-la-Cise, you have the choice of continuing the loop and returning inland to Ault, or continuing further south to Mers-les-Bains. Like many of Picardy's small fishing ports, Mers-les-Bains specialised in tourism and sea bathing, which were all the rage in the late 19th century.

Mers-les-Bains adjoins another seaside resort with an identical style, Le Tréport, which lies on the other side of an imaginary border: we are now in Normandy, where the cliffs of the Côte d'Albâtre rise up to the mouth of the Seine!