There are but a handful of places where the Rift Valley evokes its geologically violent origins with graphic immediacy. Ethiopia’s Danakil Desert is one such spot; the volcanic Virunga Range in the Albertine Rift is another. And so, too, is the most northerly landmark in the Tanzanian Rift Valley, the low-lying Lake Natron, a shallow sliver of exceptionally alkaline water that extends southward from the Kenyan border near Mount Shompole for 58km.
The Natron skyline is dominated by the textbook volcanic silhouette of Ol Doinyo Lengai, which rises more than 2km above the surrounding Rift Valley floor to an altitude of 2,960m, its harsh black contours softened by an icing of white ash that glistens brightly below the sun, as if in parody of Kilimanjaro’s snows.