A route known as the Pan American Highway stretches from the northern coast of Alaska to the southern tip of Argentina.

The one break in that 19,000 mile network of roads is in the region that connects Colombia and Panama, and therefore South and North America.

The only way to get across the dairy and gap by land is to make a 70-mile trip on foot through dense jungle that early colonizers thought was mostly too dangerous to attempt.

This year, as many as 800,000 people are expected to try, and not all of them will survive.

From KERA in Dallas, this is think. I'm Chris Boyd.

These are not athletes or explorers navigating sheer rock faces and dodging venomous snakes.

Often they are families from Latin America, the Caribbean, Asia, Africa, congregating in this

very dangerous place in hopes of making their way ultimately to the U.S. border to plead for asylum.

My guest traveled much of that route herself to learn some of their stories, which, as we will hear, are shaped by U.S. immigration policy despite the fact that the Dary End Gap lies thousands of miles from our southern border.

Caitlin Dickerson is a staff writer at the Atlantic, which published her article 70 miles in the Dary End Gap.

Caitlin, welcome to think.

Hi, thanks so much for having me.

First of all, why is there no road through the Daryon Gap?

There's no road through the Dary and Gap because of those geographical elements that you just described.

The jungle there is very, very thick. It's mountainous.

There are rivers that crisscross through it so that if you're walking and only making it a little

bit of distance through the jungle in a day, you'll end up crossing water dozens of times.

All those animals that you described, it's very, very difficult. And thus far has not been

conquered by any of the governments who, for strategic purposes, probably would have loved to

extend this road and improve things like trade. So when Colombians want to go to Panama or vice versa, they typically go by boat,

is that right? By boat or by plane. Yes. And the sea alongside the jungle is very, very rough,

but there are ways to do it by traveling when conditions are a little bit easier. And so you actually do have some migration along these boat routes as well,

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