It has a comically short main street, Rua Dr Teixeira, where the Suspira Cafe attracts the island’s bohemian set (both of them) and Cafe Açor brings in the young crowd (half a dozen of them). The Cervejaria Sao Jorge remains faithful to the Portuguese mainland restaurant tradition of serving rice and chips with every meal, and seems unlikely to succumb to the vagaries of culinary fashion any time soon.

Sit by the bandstand in the outstandingly pretty Jardim da Republica and soak up the somnolence of an island afloat in Atlantic doldrums. If the tranquility gets too enervating, a multitude of small boats in the harbour offer the latest tourist attraction catnip: whale-watching tours. In summer there are enough whales in the vicinity to pretty much guarantee a sighting.

Free whale-watching and dolphin-spotting is thrown in with a ferry ticket over to Sao Jorge’s nearest neighbours, Pico and Faial. On my choppy crossing to Horta, on Faial, the boat was escorted for some of the trip by a school of dolphins.

Horta is one of the jewels of the Azores, a breezy, pretty town battered by high Atlantic waves, and a traditional base for transatlantic yachting expeditions. Custom demands that every craft departing the harbour leaves a painting or insignia on the harbour wall, so the area is now decorated with myriad memorabilia of assorted crossings.

The other sailors’ craft conspicuous in Horta is that of scrimshaw, the arcane pursuit of engraving whales’ teeth. The foremost (or only) scrimshaw museum is above Cafe Sport on the quayside, with a collection dating back to the 18th century. It is both an impressive testimony to a patient craft and a reminder of just how whales became an endangered species. Look out for the sentimental rendition of a young Princess Diana.

Rather more ecologically sound are the botanic gardens at Flamengos. Neatly laid out, they are the focus of a campaign to protect the botanical integrity of the islands. They fight a quiet battle against the Europeanising of an archipelago that belongs as much to Africa as to the younger continent.

As a reminder, there is land on Faial that is less than fifty years old. The 1957 volcanic eruption in the sea to the west of the island forced the evacuation of villages in the area, and when the lava and dust had settled, the island was left with a 590-acre extension, a lot of ruins and the loss of hundreds of people who had emigrated to America.

It’s a memorable experience to visit this new land, look at the lighthouse still half-buried by ash, and feel the fine volcanic sand stinging your face.

Plenty of the abandoned houses are slowly rotting away, but many have been restored, some as holiday homes.

Despite the best efforts of seismologists, volcanos are still essentially capricious forces of nature. You get a sense of that destructive power at the island’s peak, 3000ft up on the caldera of the Cabeco Gordo, looking down 1,200ft into the giant crater.

In 1957 this crater began to smoke and the islanders trembled at the thought of a potential eruption. It quietened down and Faial survived, but looking into the crater you realise that the Azores are substantially more exciting than their sleepy sunspot image might suggest.

Details: Sunvil Discovery (020 8758 4747, www.sunvil.co.uk) offers tailor-made Azores holidays. Packages include a week on São Miguel from £442 per person (two sharing) at the three-star hotel Vila Nova in Ponta Delgada, including flights from London Gatwick with SATA International, transfers and seven nights’ accommodation on a B&B basis.

The 14-night Grand Tour includes six of the islands and costs from £1,340 per person (two sharing), including flights from Gatwick, all inter-island flights and transfers, and 14 nights’ B&B accommodation.

British Airways has flights to Gatwick from Edinburgh and Glasgow from £77 return.

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