Being a less than gifted painter – "Michael has made a commendable effort" was the most flattering of my school reports for art – I am rarely tempted to reach for the watercolours. But this was my overwhelming urge on first seeing the Baie de la Somme: great swathes of sea, sky, sand, mud and salt marshes in a wash of greys, blues and ochre, enlivened with splashes of green. It's technically an estuary, where the river Somme flows into the Channel, south of Calais, but the word "bay" is more evocative, capturing the area's mournful beauty.
Almost a century after the outbreak of the First World War, it's impossible to forget that the Somme was also the stage for one of the world's most infamous battles. Reminders abound: evocative museums in the towns of Albert and Péronne, trenches preserved near Beaumont-Hamel, and Edwin Lutyens's huge Memorial to the Missing at Thiepval. Yet the mouth of the Somme is unscarred.
Two contrasting towns face each other across the bay: pretty little Saint-Valéry-sur-Somme to the south faced by the resort of Le Crotoy. Outside the latter, my partner and I pitched our tent in a small campsite, joining French families from nearby Abbeville and Amiens. Down the lane was a larger site where we took in moules-frites and a hilarious dog show. Over a carafe of rosé we commiserated with the owners of a pooch which had beenawarded a rosette for 12th place, out of the field of 12.
The heartbeat of the Baie de la Somme is its tides. At its high point, the water in the bay is three miles across, but when it recedes – dropping an astonishing 10m – it reveals a vast area of sand and mud. This is when the bay really comes to life, and when harbour seals can be spotted. From the shingle bank at Le Hourdel, eight kilometres from St-Valéry, we spotted them through a telescope lounging like sunbathers.
On the dunes and out on the sand small groups of walkers were getting to know the surroundings. Closer at hand, the samphire-pickers were at work. Bent double, completely involved in their task, they were filling plastic bags with the tips of this much-prized edible plant which grows on the salt flats. Regular signs warned that picking samphire without a licence is punished by a fine. Instead, we decided to fork out for ours, as part of lunch in one of St‑Valéry's better restaurants: Au Vélocipède on Rue du Puits Salé. Inside the restaurant, which doubles as a boutique hotel, there was a small gallery devoted to local artists' work and the landscapes seemed to issue me with a personal challenge.
The food was delicious, particularly the lamb from the nearby salt meadows, although samphire, which tastes like very salty green beans, is an acquired taste. Our three-course lunch cost a reasonable €30 each.
We walked it off in the medieval streets of St-Valéry-sur-Somme. The port from which a certain Guillaume le Conquérant set out in 1066 to invade an irritating island neighbour is now subject to its own invasions of holidaymakers, particularly during August weekends. It really is very pretty: we strolled up the Rue des Moulins past fishermen's cottages smothered with geraniums to a wrought-iron crucifix, Le Calvaire des Marins. This is where wives and children of fishermen used to come to watch anxiously for the return of the boats. These days, it still provides a wonderful, panoramic view.
My sporadic attempts at painting Le Crotoy from across the bay were not going well. Georges Seurat had already made a much better job of it in View of Le Crotoy from Upstream, so I gave up and swapped the brush for binoculars. The bird life here is abundant and the place to see it is the Parc du Marquenterre. We paid €10.50 entry, hired a second pair of binoculars for €4 and set off on the 4km circuit, one of three on offer. It meandered through dunes, fields and woodland, with a half-dozen hides along the way.
During the late spring and early summer you can see nesting avocets and hear the captivating song of the nightingale. The bay is also the setting for a Bird and Nature Festival, held annually in April, with lectures and rambles around the bay. We saw the weird-looking spoonbill, egrets and flocks of oystercatchers with their distinctive black and white plumage and long, orange beaks.
You can't be exposed to so much sea without wanting to get in it. Both St-Valéry and Le Crotoy have swimming beaches, but we headed for the resort of Cayeux-sur-Mer, with its vast shingle and sand beach. It's less affected by tidal variations and it was easy to find a parking space. We crunched our way across the pebbles down to the sea, which was surprisingly warm, before enjoying a less demanding stroll along the boardwalk, which stretches for nearly 2km in front of an impressive line of 400 green-and-white painted bathing huts.
It would have made a good painting, but my efforts would simply not have been commendable enough.
DFDS Seaways (0871 574 7235; dfdsseaways.co.uk), MyFerryLink (0844 2482 100; myferrylink.com) and P&O (08716 64 21 21; poferries.com) offer connections between Dover and Calais, as does Eurotunnel (08443 35 35 35; eurotunnel.com).
The bay is an hour’s drive down the A16, exit 24.
Alternatively, the bay is a 50km drive from Dieppe, reachable from Newhaven on Transmanche Ferries (0844 493 0651; transmanche.co.uk).
Hotel Picardia, St-Valéry-sur-Somme (00 33 3 22 60 32 30; picardia.fr) has doubles from €100, room only.
Au Vélocipède, St-Valéry-sur-Somme (00 33 3 22 60 57 42; auvelocipede.fr) has doubles from €95, including breakfast. The restaurant is closed Tuesdays.
Camping La Ferme de Mayocq, near Le Crotoy (00 33 3 22 27 09 99; la-ferme-de-mayocq.com) is open from 1 April to 1 November. It costs €19 per night for two adults, a tent and car.
Seeing and eating there
The Bird and Nature Festival runs from 20-28 April (bird-nature-festival.co.uk).
Parc du Marquenterre, St Quentin-en-Tourmont (00 33 3 22 25 68 99; parcdumarquenterre.com).
The Somme Tourist Office (00 33 322 71 22 71; visit-somme.com).
Atout France (uk.franceguide.com).