The Stone Forest of Tsingy de Bemaraha — Western Madagascar

There are landscapes that look designed, and then there is this one, which looks argued about. A grey field of limestone blades stands shoulder to shoulder, every one of them sharpened to a point, with green trees somehow rooted in the gaps between. This is a tsingy — a Malagasy word for the karst badlands of Madagascar, usually translated into English as "where one cannot walk barefoot," which is the most economical description of the place anyone has managed. The blades are what is left after groundwater undercut the elevated limestone uplands from below, gouging out caverns and fissures, while rain worked down from above; where vertical and horizontal erosion patterns overlap, the rock is reduced to needles.

The formation sits in northwest Madagascar, mostly inside Antsalova District with a corner reaching into Morafenobe District, and the Manambolo River cuts straight through it. The national park is built around two of these fields, known as the Great Tsingy and the Little Tsingy, and together with the adjacent Tsingy de Bemaraha Strict Nature Reserve in Melaky Region it forms a UNESCO World Heritage Site, listed in 1990 for its geography, its preserved mangrove forests and its bird and lemur populations. What the maze does to life there is the genuinely strange part: because the summit, the slope and the base of a single limestone needle are three different ecosystems, the site holds an exceptionally large number of endemic plants and animals occupying extremely small niches — species that live on one part of one kind of rock and nowhere else on Earth.

As a jigsaw it is an unusual build, because the normal strategy of hunting for colour barely applies. Roughly two-thirds of the frame is grey stone in a thousand slightly different greys, and the thing that saves you is direction: every blade points up, so the vertical grain runs through almost every piece and tells you which way round it goes long before you know where it goes. Start with the flat blue sky along the top edge, then work the skyline where the pinnacles bite into it — that jagged boundary is the single most useful line in the picture. The green vegetation clumps are your next anchors, since each one has a distinct shape and sits in a specific notch. Save the deep interior of the stone forest for last, and work it by matching the angle of the grooves rather than the shade; the shadows between blades are nearly black and will mislead you if you trust brightness alone.