The Mekong is the longest river in southeast Asia and, by volume, the tenth longest in the world; it rises in eastern Tibet, its exact source only having been definitively located by Michel Peissel's expedition in September 1994 and its mouth is in the South China Sea - " … the river had been a central part of south-east Asia's history before its existence was known to the western world, and that later its lower reaches had been the setting for European rivalry both commercial and religious" wrote Milton Osborne (The Mekong, 2000).

Soon after breakfast we had to leave and after crossing the border back into Laos we boarded the Vat Phou, a boat 112ft long. Converted in 1993, it originally ferried teak between Vientiane and the south. The extremely comfortable boat has a wooden floor throughout, ten double cabins, each with its own bathroom and large windows and an open upper deck with rattan armchairs, sofas and tables. Laotian lunches and dinners, spring rolls, rice noodles, sweet and sour pork are served in the dining room and drinks at the ever-open bar on the upper deck.

Sitting on the upper deck just absorbing the river was one of the most peaceful things I'd ever done. We didn't go fast, and so seemed to get into the rhythm of the country we were passing through. Few houses, no roads, no industry - just terraces of vegetables and fishing boats.

"The Mekong is the ageless mother of the lowland Lao. Its annual inundation of chocolate-brown silt suckles their farmlands; and the river serves as the main commercial thoroughfare linking the Buddhist townships between China and Cambodia," wrote Christopher Kremmer in Bamboo Palace, 2003. Of course the Mekong has many other connotations as well: "American Vietnam veterans could speak of 'being up the Mekong' as a metaphor for risk and danger. And while not explicit, it is difficult to think that Francis Ford Coppola had any other river in mind when, in Apocalypse Now, he had his protagonist travel up a river to find Marlon Brando's Kurtz in surrounding reminiscent of the Angkor ruins" - Milton Osborne, The Mekong.

The 8th century temple of Vat Phou, the boat's namesake, is just four miles from the river: Added Osborne: "Wat Phou, the 'Mountain Temple' is located on a steeply rising feature that dominates the dead-flat plain running between it and the Mekong … and adding to the sense of spiritual power that the early Khmer worshippers found at the mountain, a spring provides a constant flow of pure water which flows onto a natural platform 90 metres above the plain".

A brand new museum full of sculpture and carvings from the site gives an idea of what you are about to see. The temple complex, earlier than Angkor, is a steep climb up through frangipani trees - but the view from the top and the early carvings, some almost hidden by the jungle, make the effort worth-while. The crocodile rock, which is even earlier than the temple complex, was possibly used for human sacrifice.

After leaving the boat after two magical days we spent the night on Don Khon Island at Sala Don Khone (031 251461), the only guesthouse with electricity. We reached it by local boat and although I missed the quietness of the Vat Phou, travelling through the '4000 Islands' was, as Edward Gargan described in The River's Tale (2002):

"I moved from one world to another, among cultural islands often ignorant of one another's presence. Yet each island, as if built on shifting sands and eroded and reshaped by a universal sea, was re-forming itself, or was being remolded, was expanding its horizons or sinking under the rising waters of a cultural global warming".

Seeing the rare freshwater Irrawaddy dolphins on the way to Cambodia was terrifically exciting; they are thought to be reincarnated humans and to possess a human spirit. After crossing into Cambodia we spent the night at Stoeng Treng which has nothing much to recommend it but is where we met Christopher Gow who had arranged our trip for us. Our excellent guide once we reached Cambodia was Mr T who also organises his own walking and adventure trips and whose restaurant we áte at in Steong Treng.

Christmas Day was spent driving to Rattanakiri - it is only about 80 miles inland but we bounced along for five hours on 'rock-and-roll' roads. We were heading for the Terres Rouges Guesthouse and arrived covered in red dust - I felt exactly like Norman Lewis with the exception of the colour of the dust: "We arrived filthy from our travels sweat-soaked and covered in bright yellow dust, through which the perspiration trickled down regular course" - A Dragon Apparent, 1951.

We had broken down half-way so didn't arrive until dusk - red dust poured off me in the shower and it wasn't until the next morning that I discovered that it was set on a lake and is surrounded by a lovely garden. Owned by a Frenchman the rooms are made of timber and beautifully furnished with local textiles and carvings.

Certainly the strangest, and most bone-jolting Christmas I have spent - but a great relief to be away from the commercialism of the West - it felt that Christmas was "a journey between worlds, worlds fragilely conjoined by a river both ominous and luminescent, muscular and bosomy, harsh and sensuous." - Edward Gargan, The River's Tale (2002).

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