Hanging Vines at Cenote Ik Kil

A cenote is a sinkhole with groundwater at the bottom of it, and the Yucatán Peninsula is full of them. The whole peninsula is a slab of porous limestone, so rain does not run off it — there are essentially no surface rivers in the northern Yucatán. Instead the water sinks in, picks up a little acidity on the way, and slowly dissolves the rock into a honeycomb of flooded caves. Where the roof of one of those caves gives way, the collapse opens a shaft to the sky and the water table is suddenly visible at the bottom. That is what you are looking up from here: Cenote Ik Kil, an open, almost perfectly round well in the ground near the village of Pisté in Yucatán state, a short distance from the ruins of Chichén Itzá. The name is usually translated as 'place of the winds'. A carved stone stairway spirals down the inside of the shaft to a swimming platform at water level, and the whole site is run today as the Ik Kil Archaeological Park.

The vines are the part everyone remembers. Trees and shrubs grow around the rim, where the light is, and send aerial roots down the inside of the shaft toward the water — so the walls are hung with hundreds of near-vertical strands running the full drop from the lip to the pool, which is why photographs of Ik Kil tend to look less like a cave and more like a room with a curtain for a wall. Ferns and mosses fill in behind them wherever the stone stays damp, and small black catfish circle in the water below. For the Maya, cenotes were not scenery but infrastructure and religion at once: they were the drinking water for a landscape with no rivers, which is a large part of why major settlements including Chichén Itzá sit where they do, and they were also understood as openings into the underworld, Xibalba. Ik Kil is reported to have been used for ritual purposes, and the far better documented case is the Sacred Cenote at Chichén Itzá itself — a separate cenote a few kilometres away, dredged in the twentieth century, which yielded offerings of jade, gold, copal and human remains. Many of the peninsula's cenotes are also strung along the Ring of Cenotes, a great arc of sinkholes that traces the buried rim of the Chicxulub impact crater.

As a jigsaw this one rewards working top to bottom, because the image is sorted into three bands and only the top one is easy. Start with the opening: the canopy, the patches of bright sky and the pale stone walkway along the back rim are the only high-contrast, hard-edged features in the frame, and they lock together fast. Then take the walls, and change tactics completely — colour will not help you there, since it is green on green for most of the picture, but direction will. Every root is a long vertical line, so match the strands by their spacing and their lean rather than their shade, and build them downward in columns instead of hunting across the image. Keep an eye out for the horizontal ledges of grey rock that cut through the greenery on both sides; they are the only cross-grain in that band and they are worth finding early, because they split a very large uniform area into smaller ones. Leave the water until last. It is dark, it is almost featureless, and the reflections in it are soft — the two small red buoys floating near the bottom edge are the only fixed landmarks you get, so place those first and fill outward from them.