The Largest Living Structure on Earth Imagine something so vast that it's visible even from space—this is the Great Barrier ...

The Great Barrier Reef is an underwater city built by jellyfish-like ... Everything from tiger sharks to turtles use the earth's magnetic field to navigate back to the same place.

Not far beneath the surface of the Coral Sea, where the Great ... northern Barrier Reef. Of course, to the two million tourists who visit the reef each year, the promise of an underwater paradise ...