Following is a transcript of the video. Narrator: This is the Great Barrier Reef, and it's dying. Less than 20 years ago, the world's largest living structure looked like this, and this.

For decades, the Great Barrier Reef has enjoyed World Heritage Status and been synonymous with diving, tourism and with Australia. But in June of this year, UNESCO threatened to downgrade the Great ...

For those who dream of exploring the Great Barrier Reef's underwater paradise, avoid crowds by visiting a lesser-known ...

In 2016 and 2017, marine heat waves caused by climate change resulted in mass bleaching, which killed about half of the corals on the Great Barrier Reef, along with many others around the world.

Plus, see the rest of the top 100. Watch: SpaceX Loses Contact With Starship Spacecraft Shortly After Lift-Off New fossil discovery of an early human ancestor reveals that it walked upright, just like ...

Many visitors say the Great Barrier Reef is best seen through a scuba mask, but it's no small feat to traverse the area's dive spots. When choosing which regions to explore, consider your skill ...

One of the seven wonders of the natural world, the Great Barrier Reef lies in the clear blue waters off the northeast coast of Australia. Spanning 14 degrees of latitude, this complex reef system is ...