Yeak Laom is a crater lake so evenly blown open that its shoreline looks drawn with a compass: a circle roughly 800 metres across, dropping to almost 50 metres deep. No stream runs in and none runs out, so nothing muddies it. You can see several metres down through water that reads emerald over the shallow rim and turns near-navy above the middle. Old jungle closes over the whole shore, five kilometres from a provincial capital. There are wooden jetties to jump from and a footpath of about two and a half kilometres looping the water under big trees. To the Tampuan, an indigenous people of Cambodia's northeastern highlands, this is not scenery. The ring of forest is where their spirits live, and that belief is why the trees are still standing.
The lake almost lost that protection. In the mid-1990s a karaoke bar and a brothel opened on the shore. The outcry reached the king, and in 1998 the provincial governor handed management to the Tampuan villages under a 25-year agreement, one of the first of its kind in Cambodia. Offers have kept coming: a five-star hotel plan was refused in 2018, and talk of leasing the lake to a company surfaced again in 2023. In 2019 the Environment Ministry recognised the water and its forest as a community protected area held by five villages, and those villages still run it. What they have kept is deliberately plain, down to a small centre where the Tampuan tell their own story. The basalt around the lake erupted about 700,000 years ago, in the last explosive phase of the Ratanakiri volcanic field. Come at dawn in December or January and the lake steams.