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Deirdre Mullins lives the life - and makes us very jealous.

The crew scrambled to pull and feed a series of ropes to unfurl the two sails, which became caught and taut in the wind. We were travelling at 10 knots per hour from the island of Ko Racha to Phuket. We were sailing, and it felt free.

I was one of seven finding their sea legs on a weeklong sailing trip around the northern part of Thailand's Andaman Sea. Our home for the week was a 50-foot catamaran, crewed by our Swiss skipper, Marcus, and two local men, Apple and Mee.
Most of the time we had little wind and the boat motored along without a care. But it didn't matter; every day the sun revealed itself and we cosied into the bean bags on deck, applied sun block and kicked back.

As the country becomes eaten up by mass tourism, finding unspoilt islands in Thailand is not as easy as it used to be. The northern Andaman coast is home to the five-star resorts of Phuket to the west and the busy and beautiful backpacker haven of Krabi to the east. But despite being one of the most developed bays in the country, in its heart there are dozens of uninhabited islands.
Without exaggeration, this bay is one of the most beautiful in the world. Dotted through it are jungle-topped islands, gravity-defying limestone outcrops, caves, lagoons, coral reefs and azure waters lapping on white sandy beaches.

While it was a week for slowing down, it was not one for being inactive. Most days we snorkelled, swam and kayaked. Kayaking is the best way to see the limestone tower-studded bay of Ao Phang-Nga National Park. Many of the tourists staying in nearby resorts pack into crowded boats to get a glimpse of the area, but kayakers are the lucky ones who get to enjoy the views in slow silence.

By kayak you can also reach places that the tourist boats cannot. On our first day I kayaked through a coffin-like cave so tight that I had to lie back to protect my head and back. Then the cave opened up into a stunning lagoon with turquoise water, surrounded by dramatic limestone cliffs.

That was typical of a day's activities, and so was diving off the boat for a swim, snorkelling in the coral reefs, walks and bonfires on desolate beaches, watching the sunset and, of course, eating.

Our cook, Mee, was a man of talent. He made the odd Western dish but really excelled when he cooked Thai. Tropical fruit, fresh fish, hot and tangy Thai salads, coconut soups and an assortment of curries busting with garlic, chilli, kaffir lime zest and lemongrass were served. Good, authentic Thai food like this is reason enough to come to the country.  

The first couple of days were so relaxing; I unwound and felt removed from 'normal' life. We saw very few people other than the Thai fishermen and other sailors. Thankfully, Marcus directed us to places slightly off the main tourist map. Even when we were at popular attractions, such as the film locations for The Man with the Golden Gun and The Beach, we went there at off-peak times when most of the other tourists had gone.

The nights on the boat were just as beautiful as the days. With no light pollution the sky was clear, revealing twinkling stars and planets. Just above my bunk was a hatch where I could lie back and look out while being rocked gently to sleep by the sea. It was idyllic.

During the second half of the trip we made some stops to popular resort islands which took some getting used to. Who would have thought that after only four days at sea one could become so unaccustomed to crowds?

The island of Ko Phi Phi was the most difficult transition. Arriving at the pier I was bombarded by hawkers touting for business, while the streets were packed with hordes of backpackers. Phi Phi is a stunning island, and I've heard it said that its beauty is a burden as the masses flock there for the party scene. The island was flattened by the tsunami that stuck Southeast Asia 10 years ago. There is little evidence of that devastation after a huge rebuilding programme.

Happy to return 'home', we took a short spin and anchored at a more isolated part of Phi Phi, Pileh Lagoon, also known as The Lagoon for Lovers. It was huge. In my estimation it was similar in size to Croke Park. The water was crystalline blue and surrounded by cliffs. And we had it all to ourselves. I didn't paddle but let the kayak drift in the water, enjoying the stillness that was beautifully interrupted by birdsong and monkeys howling.

Railay Beach in the Krabi province was another resort stop. It was hard not to get a strain in your neck from admiring the sky-scraping cliffs surrounding the beach. Another jaw-dropping sight was Princess Cave where Muslim and Buddhist fishermen place carved wooden phalluses as offerings in the hope of providing plenty of fish.

Just beside Railay is Tonsai Beach. It's the ultimate jungle gym for rock-climbing fanatics, and at night the beach comes alive with a chilled-out backpacker scene.

We took the dinghy from the anchored yacht to have a drink in Tonsai. Arriving on the beach I felt like a 'yachtie'. I had always admired those fortunate sailors who drift from port to port before stopping off at some tropical island for a snorkel or a barbeque on the beach. I smugly smiled to myself, thinking that I was one of them tonight.

In the bar I got talking to one of my fellow passengers, a German called Derk. He grew up in West Berlin before the Wall came down, which meant that his travel was restricted. As a child he had a poster of a tropical beach on his wall. He said that this sailing trip in the Andaman Sea had been "the stuff of dreams".

On our trip back in the dinghy that night I could see the outline of the magnificent cliffs in the moonlit sky. As the propeller ploughed through the water the sea was illuminated by phosphorescence, which left a green sparkle crackle in our wake. Derk was right, the stuff of dreams indeed.

Deirdre Mullins

Intrepid Travel ((01) 524 0071 offers a 7-day Phuket Sailing Adventure in Thailand from €1,070pp including six nights aboard a skippered yacht, all breakfasts, four lunches and four dinners, local skipper and chef. Intrepid can also arrange international flights.

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