David Attenborough is a legend, and his nature documentaries has intrigued and educated television viewers almost since TV began.

Some of his best work has been in recent years, with The Blue Planet providing some of the most fascinating television spectacle ever seen.

This video clip is from an episode entitled The Deep, which looked at the murkiest reaches of the deepest oceans, where some rather odd discoveries were made.

As well as odd shaped, and weird looking fish, there was also an underwater lake found… of sorts.

Over half a mile down is a lake of salty brine, much heavier than the water above it, which gives the illusion of a lake existing under an ocean. Amazing stuff.