When I was at junior school we studied a stirring poem by Tennyson about an Elizabethan seaman called Sir Richard Grenville and his crew, who fought a gallant rearguard action in their ship The Revenge against 53 ships of the devilish Spanish fleet to enable the rest of the English fleet to escape.

It began: ‘At Flores, in the Azores Sir Richard Grenville lay…’ That was the sum total of my knowledge of the Azores until I went there, and it’s possibly yours, so here’s a quick geography lesson.

The Azores are part of Portugal. There are nine main islands, two in the east, five in a central group and two in the west. You really need a plane to get from one group to the other, but moving between the islands within each group is a short boat journey.

They’re roughly on the same latitude as Lisbon, and Santa Maria, the easternmost island, is almost 1,000 miles from the mainland, and about 400 miles from Corvo, the westernmost.

A Portuguese poet described the islands by their colour, so that Flores is the pink island, Santa Maria the yellow island, and so on.

We visited São Miguel, the green island, and Faial, the blue island.

You couldn't argue with the poet. São Miguel is very green indeed, especially when seen from the air, the fields and smallholdings densely packed, and almost comically running right up to the very edge of the cliffs that surround much of the island.

Faial’s nickname comes from its hydrangeas. They are everywhere – in the gardens, lining every road, on every bank. They were a fine sight, even though we were there after the peak time for blooming. In July, when they are at the zenith of their colour, Faial must be a stunning sight.

Many visitors come to the Azores for the whale-watching, and it promised to be the highlight of our trip.

We made our way down to the quayside at Horta, the main port of Faial, to meet Norberto, the Whale Man.

To get an idea of Norberto, imagine that the Ancient Mariner had given up wedding-guest-bothering, spent a while in the Grateful Dead, been marooned on a desert island for a bit, and ended up looking for whales in the Azores.

After he’d given us a quick briefing about dolphins, whales and their habits (about 20 different species are found around the islands), we set out to sea. About four miles out, we came across a family of bottle-nose dolphins, which played around the boat, leaping out of the water in graceful curves. But we had come for bigger fish. Well, okay, mammals. We headed further out.

Eventually, we were nearly 20 miles out at sea. Two other boats were looking for whales nearby. The captains chattered on the radio, the boats circled, and we all, passengers and crew, scanned the sea in every direction looking for a tell-tale spout.

Suddenly, someone would see something, the boats would swing round and skid fast across the waves, only to stop when it proved to be a false alarm.

More scanning, more circling and searching. Another burst of chatter on the radio, another surge, another disappointment.

By this time, we passengers were already imagining ourselves to be Quint, the grizzled old salt from Jaws, or Captain Ahab, minus the harpoon.

Whales are not easy to find. They come to the surface briefly to blow off water, take a breath, and then head back to the depths, where they may stay for 40 minutes. Fortunately, they are sociable creatures, so if you can spot one, you may be able to find others close at hand (or should that be close at fin?).

Our guide was beginning to panic about missing our flight back to São Miguel when we finally struck gold – about half a mile away a sperm whale came up for a breather, rolled over in a stately fashion and plunged slowly into another dive. We had seen a whale.

Like all the islands of the North Atlantic, the Azores were created by volcanic activity, and it shows. The landscape is spectacular, and all the islands have their own character.

The last eruption was in 1957, when Faial gained a few extra square kilometres at one end, most of which has since been washed away again by the sea.

We visited the site of the eruption at Capelinhos. There an underground visitor centre, which tells you absolutely everything you need to know about volcanoes, has been built in the heart of the old volcano.

The landscape around has been preserved exactly as eruption left it, bare and uncultivated, with the Capelinhos lighthouse that, while battered by the blast, survived.

Back on São Miguel, there are plenty of signs of gentler volcanic activity.

We visited Caldeira Velha, where waterfalls of hot water cascade down to pools where the hardier visitors, or at least the Austrians, jumped in to bathe in the sulphurous waters.

The bubbling mud flats on the shores of Lagoa das Furnas are best visited late in the day, because the smell of sulphur clings to your clothes and hair, and you need a good scrub down to feel clean again.

Here, local restaurants place huge pots of stew into holes in the ground first thing in the morning and hoist them out at lunchtime, perfectly cooked, to serve to visitors.

And what about the food?

The cuisine of the Azores varies quite a bit. The central islands were on the old Spice Routes, and the traditional food there is therefore spicier, more like Indian or Chinese. São Miguel, however, was off the spice routes and the cuisine there is more fish-based, making much use of garlic, salt and red peppers.

I was particularly taken with the local tea-flavoured ice cream (very refreshing) and a local blood sausage, rather milder than our black pudding, which was served with slices of fresh orange. Delicious.

The Azores are not much of a destination for the sunbather, and are more likely to appeal to the active holidaymaker.

Diving is very popular from May to October, when the water is clearest. The tourist board has marked out many popular walks and trails, of varying distances and degrees of difficulty. They’re trying to encourage cycling, but you’d need to be very fit. Some of those volcanoes are steep.

If you want variety, there are two ways you can approach the Azores. You could go to São Miguel, the biggest island, which is in the eastern group, and explore that, or you could go to the central group, which are all close together, and hop from island to island.

There’s plenty of variety there. Graciosa, the white island, is a very flat island, for example, but only a few miles away Pico, the black island, has the highest mountain in the whole of Portugal.

Because they’re out of the middle of the ocean, the Azores have a temperate climate – not too hot or cold in winter or summer, or in daytime or night-time.

And paradoxically, because tourism hasn’t been greatly developed, the Azores are a great place to visit. Because at times, you may find you’re the only visitors there...