Pool builders call this cascading edge an "infinity pool". Instead of pool water lapping a wall of blue tile, one or more of the pool's sides can be allowed to overflow. So, when you bob your head above the surface, you see the water disappearing over the horizon, unobstructed by moss-stained tile. If you're dreaming of the perfect pool, you may want to include that feature. Or you could set it in a dense jungle with wooden bridges, stone paths and palm trees.

Another alternative: let Phuket's resorts do it all for you. Searching for the ideal pool - something more than just a place to swim - can be a true adventure on this island, given the many imaginative designs set amid the scenic marvels for which Phuket is renowned.

Swimming should allow you to experience body- and soul-altering, weightless relaxation. It should evoke the sense that it is good, and good for you. That you're floating toward better health, perhaps. You may also note a fishy feeling echoing through your DNA from aeons ago, before your ancestors evolved into land creatures. But that wet buzz is good only for the first 10 minutes or so.

If you're sprawling around a resort for days on end, you'll soon crave something stranger and more sensational than merely another built-in pool. Try other-worldly. Perhaps part Disney, part dinosaur park. Maybe what professional pool-builders call a "jungle pool", although they quickly warn you never to build one at home. Way too expensive. Fortunately, Phuket has something better than a jungle pool. If you know where to paddle, you can find a swim-to-me bar able that'll provide whatever you want to drink, plus a sandy beach under your feet as you step into the water.

You'll find one of the best pools at the Thavorn Beach Village, on Nakalay Bay just north of Patong. The "village" is an exclusive enclave set in a forest along a rocky coast with peak-roofed buildings where people dwell amid extravagant splendour. Some of the village's ground-floor rooms have their own door from which residents can step down into a labyrinth of waterways.

The Thavorn's pool is one of the most complicated mazes of water you'll ever explore. Lagoons taper in various directions - narrow, curving courses open onto other lagoons and cul-de-sacs seemingly ad infinitum. You encounter cloistered little waterfalls. Terra-cotta elephants spout water from their trunks. Interconnected ponds are overlooked by a restaurant here, by some chaise lounges there and a row of guestrooms elsewhere. There's plenty of opportunity to sit and be cuddled by Jacuzzis.

Vying for Phuket's first-place pool, meanwhile, you have a complete contrast. Plub Pla Resort and Restaurants accurately trumpets its "luxury hilltop botanical garden resort with panoramic views of sunrises and sunsets". Yes, that's true, but it hardly describes what awaits someone who wants all the fantasy but none of the screaming kids, beady-eyed pool attendants and swarms of culture-shocked tourists who flock to other places that sound so great. Instead, Plub Pla offers the tiniest puddle of pleasure, pomp and peace available on this island - while at the same time fulfilling its promise of sunrises and sunsets. No, this is not a pool for swimming endless laps or for mob scenes. Think zen - a pool small enough to fit in the backyard of a typical house. So what's the big deal?

To get up to this "hilltop" pool, you have to drop into first gear and climb a steep asphalt road to the Plub Pla's hidden facilities, which lie inland from Kata Beach about half-way to Chalong Bay. Up here, you have bird's-nest views of both coasts: sunrise behind Chalong, and sunset beyond Kata. The pool is the sort of high-maintenance creation that pool contractors warn against building on your own property. This jungle pool, for example, recklessly rests under lots of trees and bushes that shed tiny leaves into the water. While keeping the surface pristine presents aneternal chore for the person who nets the leaves each day, this is visually the best and most natural setting for a private pool ambiance. While you float in the shade, look up at the tangle of exotic greenery overhead and, just when you start wondering whether it's all fake, a leaf will drop and silently helicopter right down onto you.

Do be prepared for the small-is-beautiful experience. Unlike the Taj Mahal or the Pyramids, which appear to some people weirdly smaller in reality than they imagined, this pool is indeed very small. Intimate, even. It's best enjoyed alone or with a loved one. That's what makes it one of the best. Trees, bushes, ferns, a waterfall and rock garden surround a sensuously curving pool that invites oozing and schmoozing, soaking and uncloaking while you admire views of the ocean below on both sides. The trees overhead rustle in the wind. Nearby, a few wooden chaise lounges await.

The pool is actually two pools fused together, resembling a newly fertilized egg cell when it begins to divide, with the smaller glob shallower than the main oval. To emphasize the natural pond look, no walls surround this pool. Instead, the deep-turquoise tile floor gradually slopes up and out of the water to form a pebble-inlaid, slip-proof deck. Too dazzled to think Zen? Then think Tarzan, Swiss Family Robinson and Robinson Crusoe, but without the yodelling, squabbling or starvation.

The Sheraton Grande Laguna takes third place for best pool on Phuket. Just try to swim from one end to the other - it's a whopping 323 metres long, though not as the crow flies. The pool curves and spirals, expands and contracts like a mammoth boa constrictor digesting several well-spaced animals. The pool meanders under bridges and, just when you need it, slides past a raised platform where you can sit in the water and rest your elbows on a bar-top as you drink.

To woo you away from the beach, the Sheraton's pool even has its own sandy shoreline; you can walk across the sand and stroll intothe pool along an underwater slope that's also covered with sand till the pool's tile floor eventually appears. Tr?s extravagant.

If all this fabulousness inspires you to dig a hole in your own backyard and have a personal pool like none other, you may want to heed the advice of Thanusak Phuengdet, managing director of Phuket's J. D. Pools. They build all kinds of pools throughout Thailand, including an import from France that they drop into place for a cool 500,000 to one million baht. "For a jungle pool, go to a hotel or resort," Thanusak says. "It costs a lot to maintain. Maybe the plants won't grow, for instance, so you'll have to pay a lot just for the plants."

And you'll be endlessly tweezering fallen leaves out of the water. Some neighbour's kid might crack his head on those rustic rocks. And the electric bill for the waterfall will soak holes in your pocket. As for a sand-bottomed pool - it'll cost you plenty in clogged filters.

If you're wealthy, no problem. "Maybe Madonna's house ...," Khun Thanusak adds, sketching a few possibilities on the blackboard in his office. But even the Britain-based blonde singer's wet dream wouldn't have what the Thavorn, Plub Pla and Sheraton offer. For a pool to be pure paradise, you'll want to be able to come up for air and be kissed by a tropical breeze.

JW Marriott Phuket Resort and Spa: A very, very long, albeit narrow, main pool weaves in some Angkor Wat terracotta architecture -- crouched elephants spouting water from upraised trunks and turtles crawling across the water. A bicycle-drawn "cyclo" rickshaw arrives with cold drinks at your chaise lounge. Arise from such decadence and you can stroll the nearby beach.

Phuket Arcadia Beach Resort: Three big pools with all the ambiance of a big brash hotel, but there are plenty of squiggly curves and waterways to squeeze in some silly or sensuous playfulness. Big is beautiful? Only for some...

Marina Cottage, Karon Beach: A tropical hideaway set amid lush, tall forest foliage, this seemingly simple pool is all about floating on your back and enjoying the jungle, the nearby peak-r