Because the river had claimed the lives of these luckless royal ladies, the local people believed their spirits would reside in the area as guardians. The potency of the belief has never diminished, and offerings are still made daily at the spirit houses.

Another sight in Nongkhai, Wat Pho Chai, illustrates a reputed miracle which occurred here on the Mekong. In the late 18th century, it is believed, the temple's presiding Buddha image, the same 1.5-metre-high gold statue seen today, was being ferried across the river from Laos when the boat sank. The image, however, resurfaced and was enshrined in Wat Pho Chai, constructed in honour of its inexplicable power. The tale is portrayed graphically, if inartistically, in a series of garish modern mural paintings inside the temple.

The miraculous aside, Nongkhai is one of the most charming towns on the Thai side of the river. It has always been the main crossing point for entry into Laos -- the Laotian capital, Vientiane, being located just a few kilometres upstream -- and today it is poised for major growth as the site of the first ever bridge to link Thailand and Laos, completed in 1994.Increased traffic and trade due to the bridge will eventually change the face of Nongkhai, but for the moment it remains a pleasant, leafy little town with the atmosphere of a frontier post. Boom times, however, are not new to the place, and Nongkhai has long claimed regional prestige. It benefitted from the 19th-century Thai conquest of Vientiane, inheriting a significant population of Chinese merchants, and in 1953 gained even more importance when it became a railhead.

Sights in and around town include, in addition to Wat Hai Soke and Wat Pho Chai, Wat Phra That Bang Phuan, a spot especially sacred for is ancient stupa; Wat Prathat, another highly revered temple imparting a fine sense of antiquity, and Wat Khaek, a strange complex of concrete statuary blending themes from Buddhist and Hindu mythology.

A seasonal highlight to Nongkhai's attractions are the annual boat races held to celebrate the end of the rainy season in October. At this time the Mekong comes alive with scores of sleek naga-prowed dragon boats competing in a thrilling regatta. With up to 40 oarsmen to a boat, the races are exciting, though equally entertaining are the crowds lining the riverbanks, cheering on their teams and generally making merry is the typical -- and contagious -- fashion of a Thai festival.

Downstream from Nongkhai, the Mekong flows first northeast before assuming a southerly course for its long run as the eastern border of I-san. This is one of the broadest sections of the entire Mekong valley. The drainage basin stretches from Thailand's flat northeast plateau to the slopes of the mountainous ridge dividing Laos from Vietnam, while the river itself, with the exception of a few minor rapids and sandbars, runs placidly in a broad meandering channel reaching in parts a width of more than a kilometre. Fertile vegetable plots dot the banks, tomatoes being a local speciality on the Thai side.

Nakhom Phanom is the next Thai town of note and, with a fair choice of hotel accommodation, makes a good overnight stop. The town itself offers few sights and instead draws its charm from the Mekong, affording stunning views of the river and, across the water, the impressive panorama of the humped mountains of Laos.

Fifty kilometres south of Nakhon Phanom is the small town of That Phanom where, as witnessed by the huge turnout at its annual fair, a temple of the same name is one of the most revered shrines along the Mekong. The temple compound is dominated by a Lao-style spire which has a curious history.More