Huge underwater UFO base 600 km off the coast of Antarctica

Who built this underwater base 600 km off the coast of Antarctica? 


The base is approximately 700 x 500 meters with a solid structure of approximately 320x320x160 meters on top. 

The base also includes a landing platform, porthole, and building structure below the landing platform.

Could there be a connection between this base and the unexplained UFO activity around and over Antarctica? 

Coordinates: 72°2'38.19"S 162°55'41.45"W