Astonished bystanders witness an ancient iceberg break off a glacier in Iceland

Lucky hikers witnessed the breathtaking moment an enormous chunk of ice broke off the Svínafellsjökull Glacier in Iceland and flipped over.

The video, uploaded onto YouTube on Tuesday by Don Olen of Olen Adventures, shows glacial slabs breaking apart and then swallowed by surrounding waters.    

As the icy slabs started sinking, a majestic blue iceberg protrudes out of the ocean.

The bystander who captured this moment with his phone can be heard ecstatically commentating this rare occurrence ‘Oh my God, I just witnessed an iceberg breaking off a glacier!’