This is 99% invisible.

I'm Roman Mars.

Every year, park rangers and trail workers across the U.S. take part in a kind of scavenger hunt on their days off.

They're looking for a particular tool, one that's often over 100 years old, but to them

it shines like a diamond.

And with the right combination of strategy and luck, they might spot the perfect one on the

wall of a local cracker Barrel Restaurant.

That's 99 P.I. producer, Lasha Madon.

Because this hot commodity is an antique steel blade cross-cut saw.

Imagine one of those old-timey lumberjack photos, the kind where two men in Plaid are working

away at a tree holding opposite ends of a huge human-length saw.

That is a vintage crosscut.

Oh gosh.

The first saws I named, I named all with a King Arthur theme.

So I had Arthur and Guinevere, of course, and then along came Lancelot.

This is Dolly Chapman. She's worked on trail crews for more than three decades,

building and maintaining trails with the US Forest Service.

And Gareth and Lynette, who were... maintaining trails with the US Forest Service.

And Garrett and Lynette, who were a couple,

and Elaine and Percival.

And of course, I have Excalibur is my favorite axe.

Dolly is an expert at finding, using and maintaining these coveted saws.

...