Attabad Lake is twenty-one kilometres of teal water in the Hunza valley of northern Pakistan, and it is younger than most of the people looking at it. In January 2010 the mountain above the village of Attabad came down, buried houses and twenty people, and lay across the Hunza river as a dam. The river rose against it for five months. By the time the water spilled over the top, two villages and more than nineteen kilometres of the Karakoram Highway were underneath it. Most landslide dams fail within a year, and engineers expected this one to burst. A spillway was cut across the debris so the lake could drain over the top instead, and the villages below were warned. It held.
For the next five years everything that reached Gojal, the valley above, crossed the lake by boat: flour, fuel, fruit for market, patients on their way to hospital. The highway came back in September 2015 through five tunnels bored into the mountainside, and now you come out of the dark into full sun with the water below you. Painted wooden boats take you out over water more than a hundred metres deep in places, with the old road and the roofs of two villages somewhere underneath. Away from the jetty the walls of the gorge stand over you on every side. The colour wants a high sun: those walls keep the lake in shadow early and late. A path beside the second tunnel climbs a bare spur to Baskochi in under an hour, and from the top the whole lake shows, one long teal shape between grey walls with the Karakoram behind. From mid-October the poplars at Gulmit and Shishkat turn hard yellow for a month, the valley's only autumn colour. In the late afternoon the engines stop and the day's crowd drives back toward Karimabad. The lake has a clock on it. Every landslide lake fills from its upper end, because the river drops its grit the moment the current slows, so this one's life is measured in decades rather than in geological time.