This is 99% invisible.

I'm Roman Mars.

There are lots of reasons to build underground.

In Singapore, there are whole skyscrapers under the earth because the country has run out of space on the surface.

In Toronto, Canada, there's a network of tunnels called the Path that connects the whole downtown,

so people never have to go outside in the winter.

And then there is the curious architecture known as the doomsday bunker.

There's a huge amount of subterranean space that we're not aware of around us all the time.

For those of us who live in suburban and rural areas, it's not unlikely that one of your

neighbors has a bunker underneath their house that you don't know about.

This is Bradley Garrett.

I'm the author of Bunker Building for the End Times.

People have always built survival shelters to stay safe from things like

plagues or hurricanes, but in modern history we've really outdone ourselves.

There are tens of thousands of government and military bunkers around the world,

and every day people are building private bunker space,

from simple backyard shelters to luxury condos that extend hundreds of feet underground.

You know, once you start looking for bunkers,

you see them everywhere.

In this episode, Brad will be our guide to the fascinating world

of architecture for the end times, and we're going to find out why today

for going through a true bunker renaissance. Let's talk a little bit about the modern bunker as it relates to the Cold War and the

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