Fowey, and the working end of the Cornish coast

Most of what people know about Cornwall's coast comes from its prettiest half-mile: the harbour cottages, the cream teas, the light that painters go on about. What the postcards leave out is that these were working ports first, built to move things in and out of a peninsula with poor roads and an excellent coastline, and that the cargo shaped the towns as much as the scenery did. Two of the smaller harbours on a round-Britain cruise itinerary, Fowey and Falmouth, tell that story rather better than the beaches do.

Fowey, and the clay underneath it

Fowey sits on a steep-sided river of the same name, a few miles from the vast open-cast pits around St Austell where china clay, or kaolin, has been dug since the eighteenth century. The clay made porcelain possible in Britain on an industrial scale, feeding potteries as far away as Staffordshire, and for well over a century it went out largely through Fowey and the neighbouring port of Par, loaded onto coasters that queued in the harbour for their turn at the wharves. The industry has shrunk a great deal since its Victorian peak, but the white spoil heaps above St Austell, sometimes called the Cornish Alps with the same mixture of pride and irony Cornwall applies to most of its own scenery, are still visible from some way out to sea.

The town itself is narrow, steep and largely unaltered, its houses stacked above the river on streets too tight for much traffic. It was the home, on and off, of the novelist Daphne du Maurier, who set several of her books in the area and drew the great house of her novel Rebecca, Manderley, from Menabilly, an estate near the town where she lived for many years. The writer and academic Arthur Quiller-Couch, who edited the enormously influential Oxford Book of English Verse and wrote as "Q", also made his home in Fowey and is remembered there with more local affection than his general reputation might suggest.

Falmouth, and the empire's post office

Round the coast to the west, Falmouth sits on Carrick Roads, one of the deepest natural harbours in the world, deep enough that sailing ships could ride out almost any weather at anchor while they waited for orders. From 1689 until the middle of the nineteenth century this made Falmouth the base of the Post Office Packet Service, a fleet of fast ships that carried mail, and often the first news of wars, revolutions and disasters, between Britain and its colonies and trading partners. A ship bound for an uncertain destination would sometimes simply be logged as heading "for Falmouth, for orders", to be told where to actually deliver its cargo once it reached port, a piece of maritime shorthand that outlasted the packet trade itself.

Henry VIII fortified the harbour mouth in the 1540s with a pair of castles, Pendennis and St Mawes, built as a matching set to cover the entrance from opposite headlands as part of a chain of coastal defences raised against a feared French and Spanish invasion. Both still stand, squat and practical rather than romantic, and between them they controlled who came in and out of one of England's most useful harbours for the best part of four centuries.

Cornwall from a ship's rail

A cruise call rarely allows time for both towns in one day, and most itineraries choose one. Ambassador's Seaside Charms sailing, nine nights from Portsmouth, calls at Fowey between Brest in Brittany and St Peter Port in Guernsey, a reminder that Cornwall's ports have always looked as much towards France as towards London.

Bordeaux and Beyond, twelve nights from Newcastle, includes Fowey on its way back from western France, while Fred. Olsen's shorter Coast of Cornwall and the Isles of Scilly, five nights from Southampton, calls at Falmouth on its way to and from St Mary's.

Either town rewards a slow morning more than a rushed one: a walk along the water, a look at the castle or the clay-stained hills, and the particular pleasure of a harbour that earned its keep long before anyone thought to photograph it.