Hey, everybody. I hope you enjoyed this week of underground stories. If you missed some, you can go check them out.

You know, we've got sewers. We've got citrus groves. There is a whole world under there.

If you have a favorite underground place, a cave or a tunnel that you explored, I would love to hear about it.

Give me a call at 315-992-7902 and leave a message with your name and story.

You can also record a voice memo and email it to me at hello atlasobscira.com.

Okay, now we head underground one more time.

Thank you. we head underground one more time. We're underneath the city of London, 70 feet underneath it, to be exact.

And we're standing on the edge of a railway platform.

It looks a little bit like we're about to get on the tube,

but on second glance, the tunnel extending off into the distance

is a little bit small.

Behind us, workers are milling around, killing time with darts,

and then a train chugs into view.

But the train has no conductor. It has no riders. There's no people on it at all. And the

train is really small. It's this caterpillar of carts that reach about waist height, but instead of seats, each of its carts is piled high with giant lumpy cloth bags.

The workers spring into action.

They hoist the bags onto their shoulders and toss them off to the side, and in a flash, the train whisks away again.

Music And in a flash, the train whisks away again. I'm Dilan Thuris, and this is Alice Obskira, a celebration of the world's strange,

incredible, and wondrous places. And today, we are taking you to London's other underground.

A railway built for one purpose and one purpose only to keep the city's mail coming on time.

We take a trip on the London Mail Rail after this. shipping these days is an arms race.

Who can deliver the fastest?

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