This Is What It's Like To Swim INSIDE An Iceberg

From the surface icebergs are giant, majestic towers but underneath they're vast cathedrals of clear ice.

This video shows free-diving genius Stig Severinsen slowing his heart-rate to an almost unfathomable 30bps so he can dive in freezing cold temperatures and tour the huge expanse of clear ice below.

The human achievement aside, it's the iceberg that actually steals the show with ripples of razor sharp ice looking as clear as crystal in some places highlighting just how dangerous it actually is to swim among them.

The short video is actually just a trailer for what would go on to be Severinsen's world-record attempt at free-driving, it goes without saying that the man knows how to choose his locations.