Where the Mekong spreads out

At a glance

What the place actually is

Si Phan Don is the stretch where the Mekong, held up by a rock shelf just before the Cambodian border, spreads to about fourteen kilometres wide and breaks around hundreds of islands and sandbars. In the dry season there are far more of them than in the wet, which is where the name comes from.

Three islands matter. Don Khong is the largest, has a road, a proper town and more locals than visitors. Don Det is small, backpacker-oriented at its northern end, and lively in a way that suits some people and not others. Don Khon, joined to Don Det by a French railway bridge, is quieter, prettier and where most of our travellers stay.

The railway is the odd detail that makes the place. The French built a seven-kilometre line across Don Det and Don Khon in 1910 so that boats could be portaged around the rapids, which are impassable. It is the only railway the French ever built in Laos, it closed in the 1940s, and a locomotive is still sitting on Don Khon.

Which island

Accommodation across all three is simple. There are pleasant small hotels with air conditioning and river terraces, and there is nothing that would be called a resort.

What to do

• Cycle Don Khon. Flat, eight kilometres end to end, past the railway bridge, the locomotive, Li Phi falls and the fish traps. Half a day and the best thing here.
• Khone Phapheng falls. On the mainland, reached by boat and road. By volume the largest waterfall in Southeast Asia, and enormous rather than elegant.
• Li Phi falls, on Don Khon itself, a chaos of channels and rocks with fishermen working traps in it.
• A boat between the islands at either end of the day, which is when the light is worth it.
• Nothing. This is a legitimate plan and the main reason people give the place three nights instead of two.

About the dolphins

For decades the pool at Cheuteal, at the southern tip near the Cambodian border, held a small resident group of Irrawaddy dolphins, and boat trips to see them were the main attraction on Don Khon. That group is gone. The last individual known on the Lao side died in 2022, and the surviving population in this stretch of the Mekong is on the Cambodian side and small.

Boatmen still sell dolphin trips. What you would be buying is a boat ride towards the border and a low chance of seeing an animal that has crossed. We do not book them, and we would rather tell you why than let you find out from a boat.

When to come

Getting here

• From Pakse, about 150 km and three hours by road to Nakasang, then 15 to 20 minutes by boat.
• From the Bolaven Plateau, back down to Pakse and south, about four hours in total.
• To Cambodia, the Nong Nok Khiene border is 15 km from Nakasang, and Stung Treng is two hours beyond it. This is the natural way to leave Laos southbound.
• From Vientiane, fly to Pakse. The road is eleven hours and there is no good reason to drive it.

What things cost here

Pictures

When to skip the islands

• If you have under twelve nights in Laos. It is 150 km beyond Pakse, which is itself a flight from everywhere else.
• In April, when the heat is genuinely unpleasant and the river is low.
• If you want a resort. There is none, and the best room available is a good small hotel.
• If you came to see dolphins. They are not there any more.
• If sitting still for two days sounds like a waste of a holiday. That is what the place is for.

Tours that go here

• Southern Laos, 6 days - two nights here after the plateau and Wat Phou, from USD 620.
• North to south, 15 days - finishes here, with the option of crossing into Cambodia.

Questions travellers ask most

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