As a confirmed townie/workaholic, I pondered a friend's invitation to join a house party of six on the Kenyan island of Lamu for a week. In the end I did the decent thing and booked my ticket with such alacrity that it seemed only seconds later I was at Heathrow, images of White Mischief filling my mind.

We were driven by our smiling host Leslie (owner of Shela house, our home for the week) to another sweet little airport called Wilson - like Biggin Hill but with more exotic fruit juices. After a mini-flight and boatride, we finally reached Lamu. When I saw the pretty town of Shela across the water, I gasped with delight. Pearl-white buildings, bobbing boats and soft sand beckoned: the stuff of glossy brochures. No cars and no stress.

When we stepped inside Shela House itself, I gasped again, this time with awe. Tendrils of puce bougainvillea and hoya creepers framed a huge white courtyard with vibrant colour. Tantalising glimpses could be seen of several rooms leading from the upstairs balcony. Antique married with modern, aesthetics with comfort, everything you read about in style magazines. I felt myself finally relinquish the grip on my mobile phone.

"This is perfect," I kept saying, marvelling at the marbled bathrooms, pretty day beds and canopied double bed. A sprint up to the roof and I spotted the hammock. Enough said: I had arrived.

The house was next to a school and I could hear children chanting hypnotically in the distance, along with birdsong and the sound of gentle sweeping down below. As I rocked in the hammock, I felt the magic start to take hold. The next step was to be issued with a Shela House regulation kikoi - a local sarong. This banished my London worry of "what do I wear today?". The first morning's breakfast set the pace for the rest of the week. It was so delicious we had no alternative but to get up earlier the next day to thunder down the beach on a "power walk" to offset the damage. How else could we justify downing mango juice, fresh fruit and delicious variations of eggs and bacon - all served by the serene Julius? Lunches were equally irresistible.

The highlight of our days was not the beautiful sunsets, the endless virtually deserted beaches, the nesting amethyst sunbirds in huge baobabs, Whispers juice bar with its sublime banana-and-lime smoothies and coconut cake, donkey rides into town, the warm sea and soft sand, the (attempted) body surfing - no, none of these could quite compare to "Bitings".

Bitings was an event where the house party would rendezvous on the roof at seven with a G&T (or a ginger beer, if too much sun) and be served a tray of "bitings", such as sashimi, pizza squares or baby sausages. An unavoidable sense of decadence descended as we braced ourselves for another gorgeous dinner cooked by Daniel, a graduate of Nairobi's Tamarind Restaurant. We only missed Bitings once, when we were double-booked at a special bonfire feast on nearby Manda island. We sat at a table eating piri-piri (chilli) prawns and fish bhajis, chatting gently and watching the sun set and the moon rise.

A dhow took us to Takwe, a 15th-century Swahili village, where we waded through mud and mangroves to see how the town might have been before warring neighbours and the lack of fresh water drove residents to abandon ship. Luckily we didn't have to, as we sailed back in luxury, hands trailing in the water as in a Martini ad. We also popped in to Peponi's, a beachside bar and hotel whose "Old Pal" cocktails simply have to be sampled. Pretending to look out to sea, we surreptitiously gazed at the other guests. The hoi polloi and local celebrities mingle here, and it was fun to get a sense of Lamu's jet set. This was a sort of Groucho-on-Sea, but more friendly and in the open air.

The challenge of our decadent week was our group walk (read "marathon") to Kipungani Bay, 20km round the coast, which stretched my holiday mood a tad. As we strode along the beach in the blazing sun, singing marching songs from The Sound of Music, we gatecrashed a party of crabs all walking sideways into the sea to avoid us. Would that I could have joined them. They seemed hell-bent on having a merry time, which was more than I was. My flip-flops were not designed to accommodate hearty rambling on sand.

Finally we saw the oasis of Kipungani Bay Hotel, where we stopped, ravaged, thirsty and unfashionably pink. Our host didn't blink an eye as she served up Tusker beers - naturally the best I've ever tasted. Returning in a speedboat after a dip in the hotel pool seemed a much more preferable method of travelling and thankfully ensured we wouldn't be late for that day's Bitings. One night we visited an even bigger house for supper. "Beach House" nestles cosily by the shore with a beautiful jacaranda tree in its grounds. It sleeps 18 and is also owned by Lesley and her husband. Here I really felt myself becoming a true White Mischief diehard. I started to whimper at the thought of going home. How could I possibly settle for a brick patio with outdoor heater? We sat on the terrace in a semicircle of director's chairs, watching the stars, with a well-stocked bar behind us, the lapping sea in front and a swimming pool below. I felt I was in a Bond movie, and had to pinch myself.

When the week ended, I had an acceptable suntan, an ability to play poker, champion scrabble skills, a rediscovered love of sketching and was so relaxed I didn't need to speak. Lamu, don't change: I'm coming back.

FACTFILE

Checklist
Language: KiSwahili and English.
Time: GMT+3.
International Dialling Code: +254
Money: Kenyan Shilling (KSh), currently KSh118 to the UK £. Credit cards are accepted by many hotels and restaurants.
Visas: All visitors require visas, with a single-entry visa costing US$50 from the Kenyan High Commission, 020 7636 2371.
When to go The main tourist season is from January to March. The Kenyan coast is hot and humid, with average daytime temperatures of 28-33oC. During the rainy season, from April to June, the island is quieter and hotel prices drop.
Getting around Lamu can be traversed easily by foot. However, the best way to see the island is on one of its 3000 donkeys. Alternatively, take a leisurely cruise aboard a dhow.
Getting there Air Kenya (www.airkenya.com) operates year-round flights from London to Nairobi, with return prices starting from £510. From Nairobi, Flamingo Airlines (www.flamingoairlines.com) flies daily to Lamu from £107 return.
Where to stay Lamu Town has a plethora of accommodation. Top-end hotels cost from US$100+ per person, while a simple room in a cosy guesthouse costs around US$20.
Where to eat The waterfront in Lamu is lined with cafés and restaurants.
Things to do The best place to get acquainted with the town's culture and history is the Lamu Museum. The nearby Swahili House Museum is just as enlightening. Other attractions include 200 year old Lamu Fort and the Donkey Sanctuary, a haven for the island's burden-weary beasts. Water sports are available at Shela Beach.
Find out more Kenya Tourist Board www.magicalkenya.com