Insider's guide to exploring the great caves of Sarawak, Malaysia's ancient wonders

Thick with lush, primary rainforest, Sarawak’s Niah National Park covers just under 12 square miles. The park is also home to imposing limestone rock formations, meandering rivers and dramatic cliffs, but that’s not unusual for this region in Borneo. What makes Niah National Park extra special — a jewel in Malaysia’s crown — is its caves, which include not only one of the biggest cave entrances in the world, but some important archaeological sites. Here, fragments of skull were found dating back 65,000 years, making them the earliest human remains ever discovered in Southeast Asia. 

(Discover the impressive sights of Niah National Park in Sarawak)

The intrepid trek through Niah National Park also takes you on a journey of discovery, with the total walking time coming to about four hours.  From conquering wide cliff shelves beneath canopies of limestone to navigating dense rainforest, the route through the park itself is a memorable one. You’ll encounter locals selling hand-woven baskets and discover ancient cave paintings of stick figures and wooden boat coffins. Visit the caves at dusk and you will see thousands of swiftlets returning to roost. The droppings from the birds have been used as natural fertilizer since the early 1800s. For all the wonder of their ancient past, the caves are fascinating too for their more recent history and the role they play in the lives of everyday people from the region. 

(Legends of Kuching: in conversation with the craftspeople of Sarawak)

So, explore the rainforests of Niah National Park and journey to an ancient world with this five-stage guide to exploring the great caves of Sarawak.

Stage 1: Crossing the river

A two-hour drive from Miri, the Niah National Park HQ is a short walk to a jetty where the adventure begins. Here, a motorboat will ferry you across the Niah River to the trailhead. On the riverbank stands a ramshackle wooden building that was once used to store guano collected from the caves. Next to the wooden building is the Niah Archaeology Museum, where you will learn the full background to the trade. The earliest inhabitants of this region were members of the Penan tribe, and it is they who have the traditional rights to harvest the guano. In the 1980s, up to nine tonnes of guano was collected each year, but today the business is far smaller — just 10 people are still licensed to operate in the caves. 

Stage 2: On the trail

From the Niah Archaeology Museum, a wooden boardwalk takes you into the rainforest on the 1.7-mile route to the first cave. This trek is very much part of the experience, passing through dense forest where sour rotang fruits hang like orange coconuts and the red trunks of kempas trees stretch upwards and out of sight. Sections of cliff — part of the northern edge of Mount Subis — loom suddenly through gaps in the foliage, sometimes smoothed by a former river or pitted and sculpted by an ancient ocean. Elsewhere, islands of limestone appear, looking like abandoned pagan temples, strangled by creepers as thick as a leg. All around are the whoops and chirps of birds and the sibilant, electric buzz of cicadas. It’s as though the rainforest is creating an atmosphere for your arrival at the caves. At the end of this stage, you’ll be greeted by some locals selling baskets, keyrings and drinks from little tables. The boardwalk forks here — the left fork leading to a longhouse where food can be arranged and the right fork continuing to the Traders’ Cave.

Stage 3: Traders’ Cave

A few minutes further along, the trail leads to a wide cliff shelf beneath a huge overhanging canopy of limestone spiked with stalactites. This is the Traders’ Cave, where for centuries those involved in the buying and selling of edible birds’ nests would base themselves during the harvesting months. These traders lived in roofless huts and the skeletal frames of these basic dwellings — which were used until the 1970s — are still ranged along the cliffside. 

The small swiftlet birds have a pair of salivary glands which produces a sticky secretion that they use to attach their nests to cave roofs and walls. It is this ‘nest cement’ that would be used to flavour the birds’ nest soup. The process of gathering nests is dangerous and takes real courage. The roof of the Great Cave can reach up to 200ft, and licensed collectors (tukang julok) get there by climbing poles called penyulok made from pieces of bamboo lashed together with split rattan. One man scrapes the nests away and another collects them from the floor in sacks.

Stage 4: The Great Cave

Another 200 metres on, you’ll be met by the big daddy of the cave system — the Great Cave. The cave’s West Mouth entrance is among the largest on earth, with stalactites and creepers that hang like teeth. The cave was first scientifically explored in 1880, but the main archaeological excavations occurred in the 1950s and 1960s. These were led by Tom Harrisson, curator of the Sarawak Museum, and Barbara Harrisson, who worked alongside him on these pioneering projects. During a dig they discovered evidence of pre-Neolithic habitation including bone tools in an area near the cave mouth, and a Neolithic burial place further inside. The best-known find was the Deep Skull — pieces of the cranium of a 15- to 17-year-old girl that could date back 65,000 years. 

There’s an almost mystical atmosphere here as limestone stalagmites rise like statues. One area is called the Moon Cave because, in early afternoon, when the sun is at its height, a shaft of light streams through a hole in the roof like a silver moonbeam. Wooden boards and steps take you through the cave. It’s worth having good footwear because the boards are slippery with guano, and you’ll need a torch too for the darker parts.

Stage 5: Painted Cave

After 30 minutes you’ll emerge through the Gan Kira exit into sunlight and rainforest once more. It’s a walk of roughly 450 yards to the final stop on your tour. The Painted Cave is smaller than the Great Cave, but it is a veritable treasure trove of archaeology. It must have been quite a moment when Barbara Harrisson set eyes on its 160ft stretch of wall decorated with more than 100 images of horned animals, geometrical swirls and boats containing stick figures, all drawn with red plant dye. The boats are thought to represent a voyage to the afterlife, and a corner of the cave contains a series of wooden boat coffins that have been carbon-dated to between 2,300BC and 1,045BC. Remarkably, these artefacts are protected by nothing more than a simple wire fence.