Magnus Mills sails between basalt walls off Iceland
The best way to avoid seasickness is to keep your eyes on the horizon. No matter how much the boat pitches up and down, so long as you keep watching the various horizons you will be all right. I tried to bear this in mind when the captain started telling us about the rotted shark meat. "If it has been properly rotted, it is delicious," he announced. The boat surged upwards. I kept my eyes on the horizon. Again his voice came floating up over the Tannoy. "Those on the upper deck may wish to know that the next part of our voyage will become a little rougher. We are coming to a piece of the sea we call the three holes in the road." The boat duly lurched sideways.

I began to wonder if the captain was saying all this with a straight face. Or was he standing below smiling faintly to himself as he delivered his laconic remarks? I had to admit that his timing was perfect. He seemed to know the sea pretty well, too, in wave-by-wave detail. And presumably it was him doing the steering. I had not seen anybody else when we came on board; just this man turned out in full captain's uniform. Eggert, his name was. Commander of the Westman Islands Boat Trip. A brilliant seaman. Apparently with a sense of humour.

The Westmans form a chain of small volcanic islands lying to the south of Iceland. (They are called volcanic islands because they were forced vertically out of the seabed by volcanic activity.) They are steep and sheer. Which means Eggert can sail his boat very close to them.

Very close. I was looking in the wrong direction when we got to the first one and was caught by surprise when a towering wall of basalt loomed over the boat and slid slowly past. It almost looked close enough to touch. "It is close enough to touch," said the captain's voice.

"You will notice there are ropes hanging down here and there," he went on. "These ropes we use when we collect the birds' eggs. We also use them to hoist the sheep up on to the tops of the islands."

Hoist the sheep on to the islands? "There is grass on the islands and the sheep like to eat grass," said Eggert flatly, as if spelling something out. As the island receded I looked up. Hundreds of feet above me, moving carefully around on the steep grassy slopes, there were, indeed, sheep. I suppose I should not have been surprised. If people can live there, then so can sheep.

The only inhabited island in the Westman group, Heimaey, is actually still hot from the last time it blew up, in 1973. The people who live there will proudly show you their mountain, Eldfell, which almost, but not quite, obliterated their town during the last eruption. But they carry on as though nothing happened, fishing round the islands and swinging on ropes to hoist sheep.

Someone has even put a public garden in the middle of the lava that 22 years ago flowed red-hot down the mountain. Lupins, anenomes, pansies, a garden gnome. Very nice.

Back on the boat, Eggert had more things to show us. "Here is our new island. This we call Surtsey. It rose out of the sea before our eyes. It was unbelievable." Eggert was a master of the understatement. But there was more to come. He squeezed the little vessel between steeper and closer walls of rock, and as he did so he told grim maritime stories of sailors being dashed on rocks around the islands in years gone by, of stranded fishermen freezing to death on deserted reefs, and people cast adrift in boats. At last we approached a vast cave tucked underneath one of the islands.

This was Kaf Hellir. The boat moved slowly towards it. Carefully it nosed its way inside. Further and further we went, inch by inch, and then the engine stopped. And there we floated, with the water slopping against the walls. I noticed that Eggert had fallen strangely silent. I soon found out why. He appeared on the front deck of the boat wearing his captain's cap and carrying a trombone. And, as the boat slowly drifted around the cave, he began to play. A sad Icelandic folk tune it was, with long mournful notes that boomed round the inside of the cave.

The passengers watched in silence. We all knew that the boat was drifting towards the rock. The light from outside seemed to come upwards from the depths. Combined with the trombone it all had a weird atmosphere. The tune ended. People applauded. I thought to myself, "Please start the engine, Eggert."

I was thinking of the grim maritime stories. But Eggert had forgotten them and now only wanted to play his trombone. "Amazing Grace" was next. Again the walls echoed. And still we drifted. But Eggert did not seem bothered. As he played he turned slowly on the decks, watching the movement of the boat, timing the waves, until he came to the end of the tune. Then, to relieved applause, he dashed below, started the engine and steered us out of the cave again.

As I said, a brilliant seaman. With a sense of humour.

There was another cave further out called Kaf Klettishellir which he also wanted to show us, but he had decided it was getting too rough so we headed for home instead. As we sailed back towards Heimaey he pointed out colonies of puffins living on some of the islands and told how the Westman Islanders go out and catch thousands of them every year. Later, when I was going ashore, I asked him why they caught so many puffins. "We eat them," he replied. "We eat puffins, and fulmars, guillemots and cormorants."

"And rotted shark meat?" I asked.

"And rotted shark meat," he replied, smiling faintly.

How to get there

The only airline flying between the UK and Iceland is Icelandair (0171- 388 5599), which has several services weekly from Heathrow and Glasgow to Keflavik, near the capital Reykjavik. The airline offers three-night packages starting at pounds 278 from London. These are lower than the official return fares. Cheaper still is to buy a transatlantic ticket; from September, Airline Network (0800 727747) is selling flights on Icelandair to the US (Baltimore, Fort Lauderdale, New York or Orlando) for pounds 261 including tax.

What to read

Iceland, Greenland and the Faroe Islands (Lonely Planet, second edition, pounds 10.95).