I'm Rory Stewart and I grew up wanting to be a hero and I'm still fascinated by the ideas of heroism.

In my new series, I'm taking in the long sweep of history from Achilles to Zelensky and asking, what is a hero?

Simply doing your job, being a decent human being.

A true hero is someone who just kind of shines by

their own light and that light is to be recognised by others. The long history of heroism

with me, Rory Stewart. Listen on BBC Sounds. You're listening to the BBC World Service and now witness history with me Claire Bowes.

It's 75 years since the creation of the United Nations Scientific, Cultural and Educational Body, UNESCO,

which has helped the world recognise and protect its most precious sites.

In 1981, the Great Barrier Reef was awarded UNESCO World Heritage Status.

I've been speaking to conservationist and campaigner Eddie Hegel,

who helped save the reef when the Queensland State Government began looking at applications to mine

and drill for oil there in the 1960s.

Well, the man who wanted to mine it for limestone actually claimed it was a dead reef.

And that was strange because as marine biologists, we didn't know we had any dead reefs on the Great Barrier Reef.

Eddie Hegel is a marine biologist who's spent more than half a century diving the Great Barrier Reef.

I spoke to him on the beach as he looked out at the Coral Sea, the home of the reef off the North Queensland

coast.

The whole barrier reef system, at least at the time, was absolutely marvellous and it never

was a dull day where you thought, oh, well, I'm just going on the barrier reef.

It was always a very special experience and a privilege.

To him, the description of a dead reef sounded extremely unlikely.

The famous British naturalist David Attenborough filmed at the reef

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