The river that runs backwards

A lake that breathes

In the wet season, floodwater from the Mekong backs up into the Tonle Sap river at Phnom Penh and pushes it upstream into the Tonle Sap lake. The lake swells and floods the surrounding forest. When the dry season comes, the flow turns again and the lake drains back to the Mekong.

That rhythm supports one of the most productive freshwater fisheries in the world, and the stilted villages and floating communities along the lake are built around it.

Angkor

Angkor, north of the lake, was the capital of the Khmer Empire from the 9th to the 15th centuries. UNESCO inscribed it in 1992 and placed it on the List of World Heritage in Danger the same year. It was removed from that list in 2004 after a long international conservation effort.

Visit the great temples early or late in the day, and give yourself time for the quieter, outlying sites.

Luang Prabang

Upstream, the town of Luang Prabang sits where the Nam Khan river meets the Mekong. UNESCO inscribed it in 1995 for the way its traditional Lao architecture and colonial buildings fit together. The town rewards slow days: monasteries, markets and an evening climb up Mount Phou Si to watch the river.