Mount Paektu & Heaven Lake

PeaksRyanggang / Jilin border,North Korea

A volcano on the North Korea-China border holding a crater lake 384 metres deep, blown open in 946 and named in both Koreas' anthems.

September·Peaking now

Jul–Sep

The lake turns deep blue only now, between thaw and freeze. For three weeks around mid-July the alpine garden flowers at once, and all three slopes, the southern one included, are open. Come early: cloud hides the rim on most days.

Year-round The caldera, the waterfall and the steaming springs are here all year; the blue water and the bloom are not.

Mount Paektu is a volcano of 2,744 metres on the border of North Korea and China, the highest mountain of the Korean peninsula, holding in its caldera Heaven Lake, a crater lake 384 metres deep and five kilometres across that was blown open in an eruption of 946, and it is named in the national anthems of both Koreas and climbed from both sides to a rim above the water. The eruption laid an ash layer across East Asia that fell everywhere at once in a year that can be named, which makes it one of the most useful lines in the region's geology, and the two rivers that trace almost the entire boundary between China and Korea, the Yalu and the Tumen, both rise on this one mountain; the way up crosses stacked climate belts, broadleaf forest, then spruce and fir, then wind-twisted Erman's birch, and above roughly 2,000 metres a bare volcanic tundra where nothing grows taller than a boot, until the last steps end at the crater edge and the ground falls away to water lying at 2,189 metres in a bowl of bare rock, sapphire from July to early October and ice from mid-October to mid-June. The lake's only outlet squeezes through a notch in the caldera wall on the Chinese side and comes down as the Changbai waterfall in a permanent roar heard long before it is seen, and downstream groundwater heated deep in the volcano surfaces at up to 82 degrees, hot enough that the stalls beside the path cook eggs and corn directly in it. For about three weeks around mid-July the tundra flowers at once, golden rhododendron, iris and lily flat to the ground, and in winter the frozen caldera is a bowl of wind-carved white with the cloud deck often below the rim. North Korea teaches that Kim Jong Il was born in a log cabin on these slopes under a double rainbow. Paektu is a volcano with a lake for a crown, and two nations sing about it.

Worth knowing

Good to know

Give the lake more than one morning — cloud usually boils up over the rim after midday, and the odds swing wildly from day to day, so climb early and keep a spare morning in reserve.
The three Chinese slopes are not interchangeable — north for the waterfall and the hot springs, west for a long stairway to the widest rim view, south for the closest look at the water.
Dress for winter even in August — the rim hovers near freezing on a bright summer morning and the wind never really stops; in deep winter the summit drops below −30°C.
Avoid the July-August school holidays and the early-October national week — that is when the queues for the rim shuttles are longest, and a weekday outside those windows is a different mountain.

Things to do

1
Stand on the caldera rim above Heaven Lake
The last steps end at the crater edge, where the ground falls away to water lying at 2,189 metres in a bowl of bare rock. Sixteen shattered peaks close the ring, left standing when the rest of the summit went. There is no shelter up here and the wind never lets up.
2
Feel the thunder of Changbai Waterfall
Heaven Lake's only outlet squeezes through a notch in the caldera wall and comes down in a permanent roar you hear long before you see it. A trail runs up the valley towards the drop, past a bank of hard old snow that survives at its foot well into summer.
3
Climb from birch forest into Arctic tundra in an hour
The way up crosses the mountain's stacked climate belts: broadleaf forest, then spruce and fir, then wind-twisted Erman's birch, and above roughly 2,000 metres a bare volcanic tundra where nothing grows taller than your boot. Boardwalks carry you across the last of it, and for about three weeks around mid-July that grey ground flowers at once between the broken lava blocks, in what the Chinese side calls the alpine garden.
4
Boil an egg in the springs below the falls
Downstream of the waterfall, groundwater heated deep in the volcano surfaces at up to 82°C — hot enough that stalls beside the path cook eggs and corn directly in it. Meltwater runs in shallow channels past the steaming vents, and on a day when cloud hides the summit this valley is still worth the walk.