The Mekong River defines the frontier between Laos and Thailand for several hundred kilometres. A drive along the Mekong is exhilarating. The road follows the river from Chiang Khan in the north to Mukdahan in the east. Chiang Khan is a sleepy little riverside town with some fine restaurants overlooking the river.

From Chiang Khan drive east to Nong Khai, passing through a series of attractive Mekong Valley towns like Pak Chom and Sangkhom.

Sri Chiang Mai, opposite the Lao capital of Vientiane, is notable for its 'spring roll wrapper' production; note the thin discs of rice paste drying on rattan stands in the sun. Many of the inhabitants of Sri Chiang Mai are naturalised Thai citizens of Vietnamese origin - Vietnamese Catholic refugees crossed the Mekong in large numbers to escape the Communist authorities in Hanoi during the 1950s.

Beyond Nong Khai the road follows the Mekong in a long curve to the north and east before swinging south towards Nakhon Phanom.

There is little but open countryside and fine views of the wide river until you reach Nakhon Phanom, another city with a notable Vietnamese presence. This is a good place to stay overnight, with riverside restaurants offering views of the nearby, cone-shaped mountains of Laos.

About 105km further south, end your drive at tranquil Mukdahan, a ferry point for the border crossing to the Lao city of Savannakhet.