Borneo island in the extreme southwestern part of the Pacific Ocean is the third largest island in the world. Although primarily mountainous, it's also known for its beaches and ancient, biodiverse rainforest. Though it's only the third largest island in the world, Borneo is still considered huge. What makes it even more amazing is the fact that it has a mind-blowing ecosystem and incredible biodiversity! Borneo is home to countless flora and fauna species, numerous ethnic tribes, and breath-taking landscapes.