Sarawak's rugged northeastern corner hides some of Borneo's best gems for adventurous travellers. Topping the list are the world-famous caves of Gunung Mulu National Park. Unesco declared these spectacular caves and karst formations a World Heritage Site in 2005 and they are a must-see for most visitors to Borneo. There are easy caverns to explore on boardwalks, plus more adventurous caves that require technical spelunking equipment. Aside from caving, activities here include hiking, boating, birdwatching and swimming.
The cool highlands in Sarawak’s northeastern borderlands are home to remote Kenyah, Penan and Kelabit settlements. The hub of these Kelabit Highlands is the collection of villages that make up Bario, which has an airport and numerous homestay options. This region boasts some of the best jungle trekking in Borneo, featuring longhouses, rugged peaks, and primary and secondary forest.