Gunung Mulu National Park is a UNESCO World Heritage Site built around one of the most dramatic karst landscapes on Earth. The Pinnacles — razor-sharp limestone spikes rising up to 45 metres out of the rainforest canopy — are its signature image, reachable only by a demanding multi-day trek. Underground, the park holds an even bigger claim to fame: the Sarawak Chamber, the largest known cave chamber in the world by area, big enough by some estimates to fit 40 Boeing 747s.
Every evening at Deer Cave, millions of wrinkle-lipped bats spiral out at dusk in a display known simply as the bat exodus — one of the most reliable wildlife spectacles in Borneo. Clearwater Cave forms part of one of the longest cave systems on the planet, and a network of well-built boardwalks and show-cave walkways means none of this requires technical caving experience to see.
