A beautiful island that's the world's third largest is actually split between three countries.

Borneo is in Southeast is one of the Greater Sunda Islands with an area of almost 750,000 square kilometres and a population of over 23 million.

The , which is the largest in Asia, is the only one in the world to be divided among three countries - Brunei, Indonesia and Malaysia.

But despite this unique geography, Lonely Planet says that it has "some of the world's most wildlife-rich equatorial , incredible landscapes (above and below the waves) and rich indigenous culture".

Among the island's popular activities are Koisaan Cultural Village, snorkeling and island hopping, seeing the proboscis monkeys and climbing the iconic Mount Kinabalu.

The Borneo rainforest is estimated to be around 140 million years old, making it one of the oldest in the world and one of the few remaining natural habitats for the endangered Bornean orangutan.

It is an important refuge for many endemic forest species, including the Borneo elephant, the eastern Sumatran rhinoceros, the Bornean clouded leopard, the Bornean rock frog, the hose's palm civet and the dayak fruit bat.

Borneo has significant cave systems. In Sarawak, the Clearwater Cave has one of the world's longest underground rivers while Deer Cave is home to over three million bats.

The Gomantong Caves in Sabah has been dubbed as the "Cockroach Cave" due to the presence of millions of cockroaches inside the cave.

However currently the UK Foreign Office advises against all travel to parts of Malaysia and Indonesia. There are no warnings in place for Brunei.

Visitors can fly into one of several major airports in Borneo, including Kota Kinabalu International Airport (Sabah) and Kuching International Airport (Sarawak). There are countless places to stay including holiday lets and hotels.

The world's largest island is Greenland, off the coast of east Canada, and in second place is New Guinea, split between Papua New Guinea and Indonesia.

Greenland has an area of over 2.1 million square kilometers and a population of 57,000, and New Guinea has one of over 780,000 square kilometers and a population of 14.8 million.