ACTUN TUNICHIL MUKNAL

Where?   Cayo District, Belize

What?     Jungle-shrouded cave, purported gateway to the Maya underworld

THE NARROW cave entrance bulges top and bottom like an hourglass, a slender slot both in the jungle-draped limestone and, so it seems, in time itself. This spot, deep in the Maya Mountains, tucked amid the cohune palms and ceiba trees, cut off by rivers, over-swung by monkeys and stalked by jaguars, already feels far removed from the 21st century. Now, to delve deeper still. To wade into the cool, blue pool at the cave mouth, to feel tiny fish nibbling bare skin, to hear splashes echoing off the shadowy walls, to leave behind the last shafts of cheering sunlight for an altogether darker realm. Ahead is the unremitting blackness of the earth’s belly, with just pinpricks of torchlight to illuminate the strange rock formations, the shards of broken earthenware and, yes, the sparkling human bones. This is the place where the living and the dead collide for reasons not quite known ...

Central America is riddled with caves, caverns and plunging cenotes (sinkholes). Millennia of sea-level changes and rain erosion have gnawed at the region’s bedrock of porous limestone, sculpting it into a geological Swiss cheese. Fascinating for speleologists. Terrifying and irresistible for the ancient Maya.

Since around 2000 BC, various Maya groups have roamed the hole-pocked terrain of what are now Guatemala, Mexico and Belize. Subsequently, cave motifs crop up repeatedly in their culture: they are painted on vases, etched onto stelae, mentioned in songs and stories. For the Maya, Tlaltícpac was the surface of the earth and the gaps in it – the caves and cenotes – were entrances to Xibalbá, the underworld: a multi-level Place of Fear, ruled by a cohort of malign, ultra-violent gods with bone-chilling names such as One Death and Seven Death, Pus Master, Skull Sceptre and Bloody Claws. The Popol Vuh, the Maya creation story, tells of Hero Twins Hunahpu and Xbalanque descending to Xibalbá to fight these nefarious forces; after being imprisoned with bats, big cats, extreme cold and raging fires, the duo manages to beat the gods at a ball game and ultimately slaughter many of the demons before using a canoe to return to the land of the living. They are the only beings ever to escape that wretched place.

Hidden within central Belize’s Tapir Mountain Nature Reserve, Actun Tunichil Muknal (the Cave of the Stone Sepulchre) is purportedly one such gateway to the underworld. Only discovered in 1989, and opened to the intrepid public in 1998, it is thought to have been visited frequently by the Maya during the Classic period, from around AD 250 to 900, when great cities such as Copán and Tikal were flourishing. The Maya utilised caves for various functions: larders, hideaways, water sources and ceremonial sites. Actun Tunichil Muknal appears to have been the latter.

As well as being doorways to hell, caves were also considered the origin of the most essential resource. Chaac, god of rain, was thought to reside on the fringes of Xibalbá, and his watery beneficence was believed to issue from these fissures in the rocky crust.

Offerings dating from the Classic era, including snail shells, ceramic pots and pieces of obsidian, have been discovered at Actun Tunichil Muknal. Items found around the cave’s entrance date from across the entire period, but those deeper inside the system can be traced exclusively to the eighth and ninth centuries. For that brief period, something compelled those ancient peoples to take the risk and venture deeper into the underworld. And when they did so, they were not just leaving jars and stones, they were making human sacrifices. Shortly after this time, the Maya civilisation collapsed. No one knows exactly why but it’s posited that a severe drought ravaged Central America, causing the population to plummet and, perhaps, causing the desperate Maya to make more and more valuable offerings to Chaac and the demons of the deep.

Today, getting to Actun Tunichil Muknal is scarcely any less arduous than it must have been 1,000 years ago. Tours are guided, but a sense of adventure is still required. First, there’s a trek through damp, snake-slithered, mist-hung jungle. It’s about an hour’s hike, via waist-deep rivers, tangled roots, cliff niches, ancient artefacts and foliage alive with creatures: prolific butterflies and birds, maybe a coatimundi scurrying amid the trees; a jaguar sighting would be rare indeed.

At the cave mouth, there’s no choice but to sink into the chill turquoise pool and paddle through the slit into the entrance cavern. What follows is pure Indiana Jones: part-swim, part-hike, part-clamber. You’ll pass cat-shaped stalactites and rocks a-glitter with crystal flows. You’ll haul onto rock shelves, step carefully amid ancient ollas (jars) and slabs carved to represent blood-letting tools, hoping not to disturb the whip spiders. You’ll enter the ‘Cathedral’, a soaring-ceilinged space of stalagmites and calcite curtains. And you’ll duck down narrow passageways seemingly designed by the demons themselves.

In the farthest, blackest recesses of Actun Tunichil Muknal lie the bones. Around 14 skeletons have been discovered, ranging in age from infant to adult. Most appear to have been killed by blunt trauma to the head. Some are tucked into small caves and cracks; others lie spread in the open.

Most macabre and magnificent of all is the ‘Crystal Maiden’, an intact skeleton – thought to be an 18-year-old girl – from a human sacrifice made over 1,000 years ago. Now, she lies in the dust, her bones encrusted with calcite crystals, formed by the deposition of minerals over the years. They make her inert frame sparkle in the torchlight. An unfortunate victim ritually despatched to bring a glimmer of hope to a doomed civilisation, now bringing a glimmer of horror and history to this dark, mysterious place.