"Don’t worry about the crabs hiding beneath the weed – they only bite painted toenails!” An uneasy laugh went up from the 12 passengers of the Zodiac as the boatman cut the engine.

Gingerly, we stepped out into the knee deep water to land, safely unchewed, on Bryher at low tide on a still August morning. It was our third day on the Isles of Scilly, a group of five inhabited islands surrounded by islets and reefs some thirty miles from Lands End. But by now, our group of nine walkers - average age 40 with nationalities ranging from a Milan-based fashion designer to an American architect – had absorbed the laid back rhythm of island life where weather and tide rule the day. At breakfast in our B&B on the main island of St Mary’s, we would cast experienced eyes at the sky and enquire knowledgeably about the time of high water. Already the cares of mainland living seemed light years away.

Climbing up the rolling slope of Shipman Down Martin Hunt our guide, who has been walking here for nearly 40 years, pointed out the Atlantic swell rolling slowly into the aptly named Hell Bay. In winter, he said, huge waves that have had an uninterrupted run of 2,000 miles smash into the cliffs, with spray blowing right over the headland where we now stood. Around us, small stone mounds marked a large Bronze Age cemetery, testimony to the first settlers who came here from the European mainland in the 5th millennium BC. Martin, shielding his eyes form the sun, explained: “The four largest islands of the Scillies were connected 4,000 years ago by a large central plain, covered in woods when sea levels were as much as 75 metres lower than they are today. Even when the Normans invaded Britain you could still walk between most of the islands at low water.”

We spent the day exploring the island – walking through narrow lanes lined with brilliant agapanthus, climbing down over rocks to swim in deserted coves, and lunching on a beach with fine white sand. The silence was broken only by the sound of a distant boat engine, for here on Bryher there are practically no roads, the occasional tractor being used to transport supplies. Perhaps as a result the birds here are tame to the point of being pushy, and I shared my sandwich with an inquisitive and demanding thrush perched on a nearby twig.

Over the six days we visited all the inhabited islands, joining each morning at 10sn - the only rush hour in St Mary's, when visitors board the ferries at the main jetty in Hugh Town.

“The great advantage of the Scillies is that even if it’s blowing a gale you can always find a sheltered beach on the leeward side simply by walking a half hour or so”, said Martin on the day we visited St Agnes, perhaps the most unchanged of all the islands. Here, in a hot northerly wind which blew from an eggshell blue sky we walked to a secluded cove – which like most beaches in the Scillies was deserted even at the peak of the season – to dive into water so clear I could see a school of fat sea bass nosing through weeds some 15 feet below. Refreshed we came to the Gugh – a small islet attached to St Agnes by a strand covered at high water.

Facing the distant island of St Mary's stands the Old Man, a prehistoric menhir set amidst Bronze Age tombs of small chambers covered by granite slabs. In a moment of New Age madness we lay in a circle on the smooth turf holding hands with feet touching the stone, to listen in silence for a distant echo of those who had worshipped here so many years before. Sadly I have to admit that the heat of the sun and the relaxation of island life propelled me quickly into a dreamless sleep, only interrupted by cries of protest from the others as my raucous snores destroyed the peace of the moment.

That evening, back on St Mary’s, a boat left at 6pm heading into a fierce sea to follow the inter-island race of thirteen six-oared pilot gigs from a distant buoy two miles out. It was an impressive sight, with a huge Atlantic swell towering over the fragile gigs, which disappeared from view in the deep troughs. But appearances were deceptive. The long boats have a fine pedigree, having been used in all weathers for more than a hundred years to ferry pilots to ships far out at sea. The rowers pulled hard on the oars as the slender gigs sped surfing down the front of waves. To cries of encouragement, the winner finally rounded the jetty into the St Mary’sharbour at barely half a boat length ahead of its rival.

Later that night the bar of the Old Town Inn was busy with rowers quenching their thirst after the long row and I fell into conversation with John Pawley, a mainland Cornishman who had come to the islands 15 years before. What, I wondered, did he think of island life?

“You have essence of Cornwall here. Sapphire blue seas, tiny ports, rugged cliffs and a long summer with hardly any winter for our spring begins on November 5, when the first flowers are picked for the mainland markets”.

Walking back to the B&B, in a balmy night under a vivid sky full of stars, it was only too easy to see what he meant.

Need to know

Nick Haslam went to the Scillies with Adventureline Walking Holidays (01209 820847) that specialise in personally guided walking holidays in Cornwall. The six day Scilly Isles holiday costs £665 per person and includes accommodation, breakfast and evening meals, 4 boat rides to the outer islands and guiding each day. Flights/ferry from the mainland not included.

A return on the Scillonian ferry from Penzance (Quay Street, Penzance, Cornwall TR18 4BZ, 0845 710 5555, www.ios-travel.co.uk) costs £92. Flights from Lands End, Newquay, Exeter, Bristol and Southampton start from £97

Guide Book: Rough Guide to Devon and Cornwall: £9.99

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