Borneo is the third-largest island in the world, with an area of 748,168 km2 (288,869 sq mi). Situated at the geographic centre of Maritime Southeast Asia, it is one of the Greater Sunda Islands, located north of Java, west of Sulawesi, and east of Sumatra.

Sabah is a state of Malaysia located on the northern portion of Borneo, in the region of East Malaysia. Sabah has land borders with the Malaysian state of Sarawak to the southwest and Indonesia's North Kalimantan province to the south. The Federal Territory of Labuan is an island just off Sabah's west coast. Sabah shares maritime borders with Vietnam to the west and the Philippines to the north and east. Kota Kinabalu is the state capital and the economic centre of the state, and the seat of the Sabah State government. Other major towns in Sabah include Sandakan and Tawau. The 2020 census recorded a population of 3,418,785 in the state. It has an equatorial climate with tropical rainforests, abundant with animal and plant species. The state has long mountain ranges on the west side which forms part of the Crocker Range National Park. Kinabatangan River, the second longest river in Malaysia runs through Sabah. The highest point of Sabah, Mount Kinabalu is also the highest point of Malaysia.