Sumatra is the only place where tigers, rhinos, orangutans and elephants live together.
It is home to lesser-known marvels, like the proboscis monkey, sun bear, clouded leopard and flying fox bat.
 It is the 6th largest island in the world.
There are more than 15,000 known plants in Sumatra's forests; since 1995, more than 400 new species have been identified.
Sumatra is home to 201 mammal species and 580 bird species.
Critically endangered, there are fewer than 300 Sumatran rhinos and fewer than 400 Sumatran tigers left in the wild.
The Sumatran elephant is the smallest of the Asian elephants.
The Sumatran orangutan is more endangered than the Borneo orangutan.