Covering two-thirds of Borneo in four provinces, Kalimantan remains one of Indonesia’s least-visited regions. The Indonesian territory makes up 73% of Borneo Island (which is also home to Sabah and Sarawak, provinces of Malaysia, as well as the tiny oil-rich Brunei). Though it’s not as developed as the Malaysian or Brunei’s sectors of Borneo, Kalimantan has an array of natural wonders and is one of the last bastions of indigenous cultures in the world.