Gunung Mulu National Park

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.

Mulu is remote enough that flying is really the only practical option. MASwings runs daily flights in from Miri (about 30 minutes), Kuching (around 1 hour 20) and Kota Kinabalu (about 55 minutes). From Mulu Airport it's a flat, easy 20-minute walk to the park headquarters if you're not carrying too much luggage.