Paradise: A panoramic view from the beach on Koh Rong Samloem island.

A non-stop flow of Angkor beer is passed around the tourist junk. Passengers on deck stand up shouting "Cheers! Cheers!" or "Bottoms up!" Others swing and shake their bodies to the rhythms of rock.

As the vessel sails offshore from Sihanoukville beach town, we start breathing in fresh, cool air from the sea. The clinking of glasses does not stop.

About 230km southwest of Cambodia's capital Phnom Penh, Preah Sihanouk, popularly known as Sihanoukville, pulls in the tourists with its relaxed beach atmosphere. It has become one of the mot popular seaside destinations in Asia.

On the way from the airport, we even saw little monkeys jump from the large casuarina trees and flamboyant flame trees lining the road. Constructed as a port city in the late 1950s, the town, which was named after King Norodom Sihahouk, has a different look and feel to most Cambodian provincial cities.

Resort leaflets provide an insight into the port city's tourist attractions, including tropical islands ringed with undisturbed beaches and facilities for swimming, hiking, snorkelling, scuba-diving, or just sunbathing.

We took a one-day boat cruise to Koh Rong Samloem islands, one of the highly-recommended destinations not far from Sihanoukville. It has white sand, turquoise water and untouched jungles. The tour costs US$25 per head, including lunch, coffee, tea and snacks.

"This time of the year we cruise once every two days. During the high season from late November to March, the boat operates every day with crew members serving on deck," said German boat owner Robert Heiduczek, who has run the business for five years.

Tours offshore: Boat trips are available to many of the nearby islands in Sihanoukville. — Photo sihanoukville-accommodation.com

"Sihanoukville is extremely unspoiled, especially small islands like Koh Rong Samloem," he said.

Heiduczek has also set up an eco tourism village and a bar and bungalows fully powered by solar energy. "Visiting this site, you get to see marine life that you will never see on a normal coral reef dive," he added.

After passing Koh Dek Koul island, home to luxurious Mirax Resort with a night stay costing anywhere from $300 to $3,000, we docked at Pagoda Island for some snorkelling.

"Stunning coral on the rock!" said Vo Hong Van, a tourist from HCM City after pulling off the snorkel. "I even saw fish with seven colours among many others. I swim well, but wear a life-jacket so that I can slowly float around looking at fish and coral.

"I lay still with chest down and without moving my limbs so that I would not disturb a school of fish," Van said, climbing to the top of the boat to jump in for a real swim.

Taiwanese tourist Chang Shu-feng lays back, feasting her eyes on the turquoise sea as a breeze slightly blows through her long hair. She said there was nothing better than unwinding by the tranquil beach after a one-hour hiking on Koh Rong Samloem island.

Island living: Koh Dek Koul island accommodates the luxurious Mirax Resort, where a night's stay costs from $300 to $3,000. — VNS Photos Nguyen Khanh Chi

"It was suggested I do some hiking, which is very popular with European and American tourists. I decided to give it a try using a local guide," said Shu-feng.

"After our hike, we went to a river surrounded by beautiful tropical plants. The colour of the river is black. It's actually clear, but you can't see through it (because of the tanin from falling leaves). It's like paddling in a huge flow of cool black tea. It is said that if you are lucky enough you are able to monkeys and snakes.

"It was a scary but interesting experience because it is totally untouched. Also it's a good way to find out about peaceful nature of the island."

To dig deeper into the nature, Shu-feng decided to stay overnight on the islands, hiring a bungalow by the beach powered by solar panels. For the first time in life she found herself living in a truly ecological fashion in a place that has kept itself green and thriving almost since time began. — VNS