This is Side Door, a podcast from the Smithsonian with support from PRX.

I'm Lizzie Peabody.

So, let's find a place out of the wind.

Maybe under the hillside down here, yeah, we might get.

It's a problem with river valleys, kind of a wind tunnel sometimes.

You have.

It's a gorgeous day on the Patapsco River, where I'm walking with Matt Ogburn in bright sunshine

and a bracing spring wind.

Maybe we can hide behind that big rock out there.

Yeah, I like the look of that rock.

Today, it's Parkland, a nice place to swim, fish, or crouch behind a boulder to do an interview.

But 200 years ago, this river that winds through Maryland and into the Chesapeake Bay

was a hub of American industry.

Water power from its dams, powered flower mills and iron forges just outside the nation's capital.

And you won't find any commemorative historical plaque,

but it's also the birthplace of Henrietta.

We first met Henrietta in 2017.

We think she was probably about three or four years old.

So, tell me about her.

So, Henrietta is a pretty fishy-looking fish.

If you draw a simple drawing of a fish, that's kind of what she looks like.

Well, she's about a foot long, shiny silver covered in scales,

...