"So far as cave exploration is concerned, Borneo is singular. There’s no place like it under the earth.” https://on.natgeo.com/2WAuxWW

"So far as cave exploration is concerned, Borneo is singular. There’s no place like it under the earth.” https://on.natgeo.com/2WAuxWW 

https://twitter.com/NatGeoTravel/status/1113222097822801921