Sarawak Borneo’s Mulu National Park holds some of the largest and most remarkable caves in the world and the Show Caves of Mulu is not something to be missed for nature lovers and adventurers alike. The Show Caves of Mulu is widely regarded as Sarawak’s top attraction and is a Unesco-listed site.
All four of the Show Caves in the Park were moulded by the action of water dissolving the limestone and by the force of powerful rivers flowing through them, each with their own particular charm.
To visit the well-known Deer and Lang Cave, it is an easy walk along the Rainfall Discovery Walk through the lush forest and alongside rushing rivers to the entrance of the World’s largest cave passage system.
Stop by Deer Cave’s prehistoric riverbed and be spectacled at the force of water that once roared through, plummeting huge rocks and carving the scalloped walls. Above your head pillars of water stream from the roof to join the river passages that twist and turn through the mountain, constantly expanding and changing the shape of the cave.
As you walk through the cave you will hear a squeaking noise in the cave made by about 3 million colonies of Wrinkle Lipped bats exciting themselves as they sense that dusk is not far away and they begin to prepare to leave the cave to feed on flying insects. The birds you see diving through the darkness are the swiftlets returning to roost in the cave. The path continues deeper into the darkness of the cave and suddenly the Garden of Eden appears in the distance, a green oasis shining in the sunlight. Nearby are Adam and Eve Showers gushing out 30 metre columns of water to the river far below.
Deer Cave is breath-taking, huge and bold but only 100 metres away is the Langs Cave. The cave walls are beautifully decorated with long shawls, layers of rim stone pools on the floor and throughout the cave is filled with spectacular stalagmites and stalactites. In this smaller cave the bats are easier to spot, small white cave prawns hide in pools of water and shimmering near the roof are threads of web spun by the thread worm larvae waiting for a passing meal.
After visiting Deer and Langs caves, you can sit back and wait at the Bat Observatory to view the evening flight of bats out from Deer Cave. Drinks and refreshments are available.
While you wait in the Bat Observatory for the nightly exodus of bats to begin you can watch the secret life of millions of bats on Mulu Bat Cam which is a remote controlled, closed circuit TV system which takes you into the dark recesses of the cave to observe the bats ‘live,’ up close.
Each evening the bats gather at the cave entrance in large ring-shaped formations, circling higher and higher up the cliff face before moving out across the rainforest in spiraling ribbons. The bats leave the cave on most evenings between 5.30 pm and 6.30 pm but on rare occasions do not leave at all. Even more rarely they sometimes leave as early as 4.30pm.
Twelve species of bats have been recorded within Deer Cave, including the colony of Wrinkled-Lipped Bats estimated to number between 2.5 and 3.5 millions.
Going back to Park HQ is a great time to move through the forest, pinning your ears back to the calls of the frogs and insects, often seeing fireflies and stick insects.
But do take note that visitors are not permitted to transcend to any of the caves within the Park without a Licensed Park Guide.
Daily excursions with Mulu World Heritage Guides are available to all the four show caves in the Park or you can make a reservation to travel around some of the ‘wild caves’ on a guided Adventure Tour. (‘Show caves’ have timber/concrete pathways and artificial lighting – ‘wild caves’ do not.)
Do ask around at the Park Headquarters office to register and to pay your park entry and Guiding Fee. Unless you are a large group, reservations for the show caves are not necessary.
Show cave tours are also offered by local Tour Operators using Licensed Park Guides.