Koh Phi Phi comprises a small group of islands in the Andaman sea between the provinces of Phuket and Krabi, of which Phi Phi Leh and Phi Phi Don manage to hog the limelight for much of the time. Both of these islands, in keeping with everything else jutting out of the water in this part of the world, are ridiculously spectacular in a way you can't quite picture until you're standing on a boat staring at them in disbelief, and it is to their eternal merit that the Thai authorities have recently become really quite protective of them. Tourist boats regularly sail back and forth between Phi Phi Don and Phuket, offloading vast amounts of visitors who spend their days lazing about on the perfect white beaches pretending not to have heard from a bloke up the pub that much of the sand is comprised of parrot fish droppings. To be honest, if you're the sort of person who goes through life worrying that everything you touch might be something gross, you're probably better off never getting out of bed in the morning. In that way, you might eventually end up covered in bed bugs and learn the true definition of irony. And if anyone ever tells you that white sandy beaches are made up entirely of parrot fish droppings, just ask them where they think all the crushed sea shells end up.

I mentioned that the Thai authorities have recently taken something of an interest in protecting the islands of Phi Phi from the dangers of tourism, in an attempt to prevent one of the most perfect ecosystems on Earth from becoming polluted by discarded crisp packets and uneaten fries. Apart from the obvious precaution of posting signs everywhere threatening hefty fines for displaying anything less than complete respect for the environment, which does sort of assume that anyone is going to take the blindest bit of notice, the government has also taken the unprecedented step of declaring Phi Phi Leh to be almost entirely off limits. These days, tourist boats are restricted to Phi Phi Don, and anyone wishing to visit its beautiful untouched neighbour must charter their own boat and make sure they've got a signed permission slip from either the Buddha or the spirits of of least three of their ancestors. Okay, so I might have made that last bit up, but getting to Phi Phi Leh isn't something you're going to be able to do unless you can afford your own boat, which rules most people out - and even assuming that you're rich enough to get there, leaving the island with so much as a single shell in your pocket could result in a period of reflection in a Thai jail cell, so you might want to watch "The Bangkok Hilton" a couple of times on DVD before you even think about taking any souvenirs away with you.

Unfortunately, when you're the proud owner of an untouched ecosystem of crystal clear waters and pure white sandy beaches, you may quickly find yourself in demand from people with enough money to make you question your environmental morals. This appears to be what happened when Hollywood stopped by one day with a suitcase full of banknotes. In 1999, the Thai authorities were visited by a group of smartly dressed men from Los Angeles who asked nicely if it would be alright if they borrowed Phi Phi Leh for a bit. They mentioned casually that they'd probably want to rip up a lot of the trees and completely bulldoze the beach, but not to worry because they would put it all back as they found it afterwards. Quite how they intended to put fully grown trees back where they found them is beyond me, but that's what they promised. Hollywood understood that Phi Phi Leh was already a paradise on Earth, they explained, but what they really wanted was a paradise to match the script - and the only way to have this was to knock down paradise and build a new one in it's place. One of the smartly suited gentlemen then waved a suitcase full of banknotes at the Thai environmental representatives across the table, with the result that they couldn't wait to sign the deal fast enough. I can actually see eyes rolling up into heads as they are replaced by dollar signs to the sound of a cash register opening. After filming was completed, questions were asked about whether or not Phi Phi Leh had been successfully restored to its previous state, and lawsuits dragged on for many years - so the next time you sit down to watch "The Beach" with Leonardo DiCappuccino, or whatever his name is, you might like to spare a thought for the island on which it was filmed.

One of the most delightful elements of any trip to Phi Phi Don is actually getting to the island from the boat. The captain can't take you right in to shore for obvious reasons - getting home again tends to become something of an issue when your boat is wedged up to its keel in wet sand - so everyone has to disembark onto a raft some distance from the island, from where they are rowed the rest of the way. If you happen to be travelling with your significant other - a curious expression which appears to label anyone you aren't in an intimate relationship with as unimportant - you probably couldn't ask for anything more romantic than to arrive on a deserted paradise island on a raft. Of course, you have to ignore the fact that you're crammed onto the thing with about 100 other people and that you have to walk some distance around the perimeter of the island before you can find anywhere with any sort of privacy, but still - it's the thought that counts. On the return trip this evening, in what I can only describe as an attempt to capitalise on the effect a perfect sunset can have on courting couples, we were collected from the island and taken back to the boat on individual motorised gondolas. This is probably the sort of thing you would talk about for years in hushed tones while discussing the most romantic holiday of your life, but unfortunately on this occasion our gondola broke down unexpectedly half way back to the boat and we found ourselves stranded some distance away while everybody else got back on board and stood around on deck laughing and pointing at us for half an hour.

There isn't an awful lot to do on Phi Phi Don, but that's sort of the point. You don't go to a deserted paradise island looking for multiplex cinemas and bowling alleys. Once on shore, the tour guide gathers everyone together and explains where everything is, but this doesn't take very long because everything is within about ten feet. You can laze about on a deckchair soaking up the sun, which is particularly unforgiving unless you've emptied an entire tube of lotion over yourself before arrival, or you can grab a snorkel and float about looking at fish. That's about it. The perfect white sand is, of course, the temperature of molten lead, which means that any attempt to get off your deckchair and go anywhere involves a lot of hopping and screaming, but when you're in paradise you tend to let these things go. I discovered, after breaking the land speed record running down to the shore, that if I stood waist deep in the crystal clear water holding a piece of bread then I would immediately be surrounded by what seemed like thousands of multicoloured tropical fish. This is an experience I will not soon forget, and one which I find it hard to believe isn't mentioned in any of the guidebooks. It's hard enough to believe that the sand is so white, or the sea so clear, or the sky so blue, but this really completed the image of paradise for me.

On the way back to Phuket, we stopped briefly at a deep cave on the far side of Phi Phi Leh where we had the opportunity to pretend we were pirates for a moment. Hidden around the back of the island is a rickety dock, seemingly not quite strong enough to hold an average sized dog and jutting out into the sea from a concealed cave entrance as though not wanting to be found. This hap-hazard construction of rotting planks and random branches serves as the only entrance to the cave within and really does give the impression of having been lifted directly from Pirates of the Caribbean. The dock also looked as though it might fall into the sea at any moment, leading many of us to eye it with suspicion and question whether it was wise to leave the boat at all. If our tour guide hadn't sworn to us that everything was above board, I think I might have suspected that this was the entrance to the headquarters of some sort of secret island drug running cartel. In fact, when we finally built up enough courage to brave the dock, we found ourselves being led through the entrance to a large chamber known as the viking cave, the name coming from the mysterious drawings of viking longships which adorn the walls. Nobody actually thought to tell us this at the time, however, and we quickly began referring to it amongst ourselves as the bird cave, which seemed to be a much more appropriate name. Fifteen meters up, thousands of swallows make their homes on ledges around the walls, and the cave is alive with the sound of their tiny wings as they swoop in and out through the narrow entrance. The cave itself is described by many as breathtaking, although I suspect this is more to do with the impressive entrance and the presence of the birds inside rather than the cave itself which is, to be honest, just a large cave. What makes the viking cave rather unusual, however, and the thing which brings visitors here from far and wide, is the ridiculous lengths to which locals go in order to collect the nests of innocent swallows who want nothing more than five minutes peace to raise a family. Bird's nest soup is so prized by the Chinese, who will apparently eat just about anything, that people are willing to risk their lives on a daily basis climbing rickety bamboo scaffolding to reach the nests and extract them from their rightful owners. They do, our guide was at pains to point out, leave the birds alone until the chicks hatch - but as soon as they've left the nest then a carefully trained team of nest snatchers are straight up there to ensure that Mr and Mrs bird come home to find the house gone. Birds nest soup is one of the most expensive animal products on the planet, with a kilogram of nest selling for between $2,000 and $10,000 depending on type. In a restaurant in Hong Kong, a bowl of birds nest soup could easily set you back $100, so it's easy to see why these people feel the need to risk life and limb in pursuit of their cut - and as long as they don't actually disturb the birds, it's hard to find any justification for telling them to stop. Still, it does raise an interesting moral dilemma - as long as someone is willing to pay for bird's nests and that money helps to provide for families who might otherwise find it difficult to survive, where do you draw the line?

After about five minutes of wandering around the viking cave, watching locals climbing the intricate web of bamboo scaffolding which criss-crossed the walls, we were about to leave when a large part of the construction suddenly came crashing down into the middle of the chamber, where it narrowly missed a couple of our group who were lagging a little behind. This fazed our guide for all of about a second before he laughed heartily and told us that this sort of thing happens all the time. If you visit the viking cave, take your own safety helmet.

About Simon and Burfords Travels:

Simon Burford is a UK based travel writer. He will be re-publishing his travel blogs, chapters from his books and other miscellaneous rantings on these pages over the coming weeks and months, and the entry on this page may not necessarily reflect todays date.