Between the 16th and 19th centuries, millions of captive Africans were forced onto slave ships and trafficked across the Atlantic Ocean.

As many as a thousand of these ships sank on the journey, and fewer than 20 of them have been found and properly documented.

For our series, Race Matters, I recently sat down with National Geographic Explorer and writer Tara Roberts,

who has been traveling the world documenting these underwater wrecks and the intrepid group of

primarily black divers working to uncover them. She tells these untold stories in her new memoir

written in the waters. Tara, thank you so much for joining us.

Your journey that you relay in this book took you across four continents,

but you got the idea for the project that became the book here in Washington, D.C.

Tell us about that.

This was in 2016, and I got offered tickets to go and visit the National Museum of African American History and Culture.

And it was there that my life completely changed.

I saw a picture of a group of primarily black women in wetsuits on a boat.

I'd never seen a picture of black women in wetsuits on a boat before.

So it really struck something in me.

I discovered that they were a part of this group called Diving with a Purpose,

and that they spent their time searching for and documenting slave shipwrecks around the world.

And that just, it floored me and made me want to be a part of that work some kind of way. When did you realize

that your story and the histories that you were telling were all intertwined and could be part of

this narrative? It wasn't until I started to meet descendants of people who were on the ships

that I started to think about my own ancestry, which is something that I didn't

think about from the start, which maybe is a little surprising. I mean, I am a black woman,

and it is the slave trade, but I just didn't think about it personally. And then traveling

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