Si Phan Don, where the river gives up

What Si Phan Don actually is

At its widest, just before the Cambodian border, the Mekong spreads across about fourteen kilometres and breaks into hundreds of channels and islands. In the dry season there are more islands; in the wet, fewer. Four thousand is a way of saying too many to count.

Three islands take visitors: Don Det, which is the backpacker one; Don Khon, which is joined to it by a bridge and is quieter; and Don Khong, which is bigger and has almost no tourism at all. We use Don Khon.

The interesting history is French. In 1893 the colonial administration built a seven-kilometre railway across Don Det and Don Khon — the only railway ever built in Laos — to portage gunboats and cargo around the falls, because the Mekong is not navigable here and never was. That single fact is why the French never got their trade route to China. The rails are gone, the embankment and the bridge remain, and you cycle along it.

How many nights

Two nights is enough: one full day for the islands, the railway, Li Phi falls and Khone Phapheng, and an afternoon on the water looking for dolphins. Three is better if the point is to stop moving, which for a lot of people at the end of a long trip it is.

One night is not worth the journey. Pakse is three hours away by road plus a boat, and the last stretch is not fast.

This is the slowest place in this whole region. There is nothing to do in the evening and no reason there should be.

What is actually here

Khone Phapheng falls

By volume the largest waterfall in Southeast Asia, and it is not a drop so much as eleven kilometres of rapids and cataracts across the whole width of the river. In the wet season the noise is the thing; you hear it before you see it. It is on the mainland, about forty minutes from the island by boat and road.

Li Phi falls

On Don Khon itself, at the end of the old railway line. Smaller, and reachable by bicycle. The Lao name means roughly “spirit trap”, and the fishermen work traps in the rapids in a way that looks impossible.

Irrawaddy dolphins

A small population lives in the deep pool at the southern end, on the Cambodian border. The Mekong population has recovered to somewhere above a hundred animals from a low of about eighty, which is better news than this species usually gets, and they remain hard to see. We put you on the water at the right hour, in a boat that keeps its distance, and we do not promise a sighting. Anyone who does is guessing.

Bicycles

The way the islands work. Flat, unpaved, and the whole of Don Khon is rideable in an afternoon.

When to go

How to get there

Pakse is the access point. It has an airport with flights to Vientiane, Bangkok and Siem Reap, though not many of them — build in a connection with margin. From Pakse it is about three hours south by road to Nakasang, then fifteen minutes by boat to Don Khon.

Overland from Cambodia, the Nong Nok Khiene – Trapeang Kriel crossing is about forty minutes south and is open. It is one of the few land borders where the Lao eVisa is valid.

There is no useful road from northern Laos: Luang Prabang is about 900 kilometres away and the only sensible link is a flight via Vientiane.

What things cost

Photographs

When to skip Si Phan Don

• If you have less than three days to spare. The journey from Pakse is half a day each way.
• If you need reliable electricity and internet. Both are approximate.
• If you want a comfortable hotel. The best on Don Khon is a good bungalow.
• If you are counting on seeing dolphins. The odds are decent and they are odds.
• March to May if heat is a problem. Forty degrees on a treeless island is a lot.

Tours that include Four Thousand Islands

Two nights at the end of the eleven-day Vietnam and Laos overland route, which reaches southern Laos through the Lao Bao border. It does not appear in the northern routes because it is 900 kilometres from Luang Prabang.

Questions travellers ask most

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