Bonjour, Guten Tag, Good day to you!" said the cab driver. "And a good day to you," I replied. "American!" he continued. "No, English," I countered. "American English?" "No, English English."

The confusion was understandable. I had just arrived in Cape Verde and the English don't come here. Even before departing I realised I was boldly going where not even an Australian backpacker had gone before. The first travel agent I called tried to book me a flight to the West Indies (the islands are actually 500 km west of Senegal's Cap Vert, hence the name); the nurse in the immunisation clinic said I was the first person in her 10 years there to ask about the necessary jabs (none). Even Stanford's, London's finest map shop, couldn't come up with the goods. The best they could offer me was a 19th-century naval navigation chart.

Cape Verde is made up of nine main islands split into two groups: the Barlaventos (Windwards) and the Sotaventos (Leewards). The Portuguese discovered them, uninhabited, in 1455 and imported West African slaves to establish the first European colony in the tropics there seven years later. The archipelago was ideally positioned to act as an entrepot for the slave trade between the Guinea Coast and the Americas but, as slavery declined, so the islands slowly slid into poverty and obscurity. Even independence in 1975 failed to raise Cape Verde's profile.

Arriving at the international airport on Sal, you could be forgiven for thinking that the islands deserve this obscurity. Sal, meaning salt, is a bleak slab of red rock and dust. Yet its major function is to act as a base marker: nothing else on Cape Verde will be this dull.

Most visitors immediately take an internal flight to one of the other islands. I opted for the largest, 60km-long Santiago. It was here that Charles Darwin landed in 1832, and the first chapter of Voyage of the Beagle is devoted to his observations of the island, as relevant now as then: " anyone accustomed only to the English landscape, the novel aspect of an utterly sterile land possesses a grandeur which more vegetation might spoil."

There is no avoiding the fact that Cape Verde is gaspingly arid and unable to support its 350,000 population. Native poets write of how the goats have taught the people to eat stones. But stones are not enough and, despite massive emigration (more Cape Verdeans live abroad than on the islands), the country receives the highest per capita aid in Africa.

Six of the Cape Verdes - including Santiago - are volcanic in origin, with beaches of scorching black sand or rock, but Tarrafal is blessed with a perfect crescent of white sand fringed with coconut palms and backed by a discreet holiday village and a clifftop restaurant.

West of Santiago lies Fogo, most enigmatic of all the islands. Fogo is a volcano - the name, appropriately, meaning fire. It last erupted in 1995 and tiny cinderblock houses cling to its precipitous, lava-stained slopes like parasites. To make the long, tortuous trip into the volcano's crater is a humbling experience. I hitched a ride in the back of a World Food Programme truck and sat among tins of Japanese mackerel, French cooking oil and Finnish luncheon meat as we slowly climbed over 2000 metres. The scene that greeted us as we struggled over the crater rim was straight out of darkest Dante. Colossal shards of twisted, swirling laval rock and towering black dunes stretched all around while ahead of us, like a dark sentinel, the volcanic cone rose a further 1000 metres. Most extraordinary of all is that people still live up here. In the midst of this otherworldly gloom stands the village of Cha das Caldeiras where black dust blows through the streets as children play in the shadow of the volcano.

All the islands have tangibly different characters. Compact, hilly, densely populated Brava has long been the most domesticated and cultivated. Its pretty capital, Nova Sintra, has been described as not so much a collection of houses with gardens, as a huge garden with houses in it. Sao Nicolau, in contrast, is utterly desolate, yet its gaunt, craggy mountains give it an undeniably powerful presence and, to ascetics at least, beauty.

In the same mould is the barren island of Sao Vicente, virtually synonymous with its main town Mindelo, where 95 per cent of the population live. Mindelo was a creation of the British who set up one of the world's largest coaling stations for ships here in the early 19th century. It's still a bustling port, modern and cosmopolitan by Cape Verdean standards, but with a relaxed, almost Mediterranean atmosphere.

The Cape Verdeans are surprisingly bad sailors for islanders. During the one-hour crossing of the, admittedly choppy, channel between Mindelo and the island of Santo Antao, a fellow passenger joked that the only reason his people hadn't left these islands long ago was that they couldn't face the journey.

Or maybe it's because they know the secret of Santo Antao. This mountainous island, the second largest, presents the bleakest of faces, but as our minibus reached the shoulder of the central range, a magical transformation took place. Trees started appearing. Not the usual scraggy acacias but pine, cedar and eucalyptus, and not just the odd one but whole forests. As we descended, a stupendous landscape opened up of cloudbursting peaks and ridges, and dizzying vertical drops of hundreds of metres - and everything cloaked in green. As someone who has seen the Grand Canyon, I can say without fear of hyperbole that the landscape of eastern Santo Antao is every bit as staggering and all the more thrilling for being so unexpected.

This was a fitting climax to a memorable trip. These unassuming, unspoilt little islands, lost in the Atlantic, are a revelation.

How to get there

The only easy way to reach the islands from the UK is via Lisbon on TAP Air Portugal. The airline has direct connections from London on Sundays and Thursdays: you leave London at 1.50pm, arrive at Lisbon at 4.20pm, wait for five hours and finally arrive at Cape Verde at 11.30pm.

For information on schedules, call 0171-828 0262. For prices, call the airline's fares department on 0171-630 0900. Until 31 October, the fare is pounds 1,174.70 return, including an elaborate selection of taxes. To qualify for this, you must stay away for as minimum of a week and a maximum of two months.

Who to ask

Further information (but not much) from the Portuguese National Tourist Office, 22 Sackville Street, London W1X 1DE (0171-494 1441). This week the average "stacking time" for callers was about an hour, so you may find it cheaper and easier to write.