From there we progressed up the coast to Haad Salad, a failsafe holiday spot populated by families and students studying at the local yoga academy. After missing out on accommodation on the northern beaches due to the Half-Moon Party, something we were eager to avoid, we stumbled upon our lucky find early: Bottle Beach.
With fine white sand and turquoise sea it's a miracle this place has so far eluded developers, which perhaps explains why it's mostly young backpackers here. The roads are still under construction so although it's not as hard to get to as the beach in Garland's book, it's still a bit of an adventure of taking a spluttery old longboat from Chaloklum at the north of Koh Phangan. With just three accommodation options on the beach (our beachfront bungalow was $12 a night) and not much other than a volleyball net on the beach, there's literally nothing to do but eat, drink and unwind.
Travelling without a fixed itinerary is liberating but opening yourself up to that element of surprise can lead to dangerous situations, and in our case, murder. Arriving on Ko Tao after the long journey from Bottle Beach, we finally found a cheap room.
While most visitors to Ko Tao come to check out the underwater wildlife, we didn't need scuba gear for that. There was a gecko on the wall of our bungalow when we returned from dinner. Not one of those cute little critters. This was the size of a human forearm, and although it wasn't making that hideous croaking noise that suggests they're keen to mate with a tractor, there was no way I was going to sleep with it in the room.
When the friendly proprietor arrived at the door with a broom, we thought he was just going to give it a nudge. Instead, he let out a blood-curdling yelp and wacked the gecko repeatedly until the poor thing was writhing on the ground. Mortified, we left as soon as possible, on to Koh Samui, and a flight to Phuket.
Phuket's reputation as the Vegas of Thailand precedes it. "Have a gander at these suits, mate," called one of countless Thai salesmen as we wandered past the shops, sports bars and ladyboys prancing down the main street. "Not Aussies, mate," we replied.
But we'd arrived at the one time of the year when the main beach at Phuket could just be the best place to be in Thailand: Thai New Year, or Song Kran, the water festival. Although its origins sound purely cultural, locals celebrate Thai New Year by throwing water over each other with the intention of spiritual cleansing.
This inescapable baptism usually comes care of an ice-filled water pistol after a few too many of the local Chang beers. Song Kran may just be the one time in your Thai beach holiday when you really get to mingle with the locals. Everyone gets soaked. Everyone gets a little cheeky. Everyone walks around with a big grin on their face.
Not so good: strolling through the streets to the beach the morning after. There's nothing quite like the smell of steamy, waterlogged rubbish to go with your hangover. It's also advisable not to travel during Song Kran, particularly on an open taxi truck, unless you fancy being a sitting duck on the slowest commute of your life.
Heading north, we were pleased to stumble upon Phuket's Bang Tao Beach, a rugged, silvery beach on the northwest coast. Two hours away by ferry is the island hardest hit by the tsunami.
Ko Phi Phi might not seem the natural choice on which to take a snorkelling trip but after our pathetic non-attempt to dive at Ko Tao, it became a mandatory activity. Having seen tourist-packed Maya Bay (where The Beach was filmed), we got off the beaten snorkelling track with our own private longboat driver, Dee.
From Phi Phi Don Beach on the northeastern tip of the island we headed to Bamboo Island, and after getting our water wings among the throngs of Japanese tourists, decided we might as well be at Maya Bay. Dee was keen to show us Moskito Island, with water so clear it was easy to spot the thousands of spiky kina, schools of feeding fish and angular brown corals.
It might have had something to do with the four Thai men huddled around a smoky fire on the beach, or maybe it was the sheer, scrub-covered cliffs that rose from the sand at right angles but on Moskito Island it felt far wilder and more remote than Maya Bay.
Getting to Koh Chang requires a bit of patience for those not on a budget to fly, or who, like us, spent their money travelling through Cambodia, Vietnam, Laos and the rest of Thailand.
Keen to end the trip the way we'd started, we took a five-hour bus ride from Bangkok to Trat, followed by a minibus to the pier, car ferry to the island and a taxi truck, which finally brought us to the most mountainous and pretty island we'd seen.
Although flash new hotels are springing up along its lush coastline, the singular road and hairpin bends give the feeling you're in the middle of nowhere.
And when the power went out at our beachfront mid-range hotel ($120 a night at Siam Beach Resort) due to a car hitting a power pole, it became obvious that a) we should have stayed in a hotel with a generator and b) this is not the island to hire a scooter.
Even walking from beach to beach is tricky if you're using the roads.
Whether it's a rocky outcrop at the southern end of Koh Chang or a stretch of uninterrupted sand, it's best to find a beach and stick to it. For us it was a slightly leaky but comfortable, air-conditioned room on a wild, palm-fringed beach, where we dined by lantern light.
Stunning though Chaweng is, we'd almost written off the touristy Koh Samui but ironically, returned to the island for our last week of freedom. This time we stayed at Lamai, the second-most popular beach, which, though populated by lots of other tourists, was great for swimming, eating and exploring the rocks.
After three nights in a four-poster bed at Samui Sense, we moved to the cheaper Sea Breeze Bungalows. There was a hole in the floor by our bed and a modest bathroom but our accommodation was relaxed, the food cheap and the guys who ran the place friendly.
A day trip to Big Buddha beach showed there's more to Koh Samui than the main beaches, just as there's much more to the south of Thailand than one island can offer.
CHECKLIST
Getting there: Qantas has daily flights to Bangkok via Sydney from Auckland and Christchurch.
The quickest way to get to the islands is to fly from Bangkok to Koh Samui or Phuket on Bangkok Airways, Thai Airways or Air Asia. If you've plenty of time and no fixed itinerary, it's easy to book flights online on arrival. From Koh Samui you can reach Koh Phangan and Ko Tao by ferry. From Phuket you can reach Ko Phi Phi by ferry and to reach Koh Chang you can bus or fly from Bangkok to Trat, then take a ferry.
Best time to visit: November to March is recommended to avoid the rainy season (June to October). However, it's quieter from March to May when the weather is at its hottest, and you'll be there for the fantastic Songkran festival from April 13-15.
Further information: Check out the comprehensive Thailand travel guide.
