This is 99% invisible. I'm Roman Mars.

It's hard to overstate the vastness of the Skid Row neighborhood in LA.

It spans roughly 50 blocks, which is about one-fifth of the entire downtown area of Los Angeles

In some ways the streets of Skid Row are a bit like other parts of LA

That's reporter Car Carla Green.

There are corner stores and street vendors selling everything from jewelry to loose cigarettes.

They're old brick townhouses filled with low-income housing.

There are parks where grown-ups gather to talk and children gather to play.

But it's also very clear when you've entered Skid Row. For one thing, there's the smell.

The streets of Skid Row often stink of urine and other excrement, baking

under the hot Los Angeles sun. The gutters are lined with trash. And the sidewalks are mostly,

and on some blocks entirely occupied by people's makeshift homes.

A dizzying array of tarps and tents stretch out for blocks and blocks, one structure jutting up against the next and the next.

And there are lots of people on the street, many of them pushing special red shopping carts.

The carts are handed out by a local advocacy group because the police used to arrest people for having what they believed were stolen shopping carts.

And so all the person got to do is just be homeless and come here, you know stand me and they register to give you a shopping cart.

And people use it to push their property around

and stuff like that in.

And the cops hate them.

That's General Doggan, walking around Skid Row with me.

He's a community organizer and lifelong resident of the neighborhood,

who's lived in both low-income housing and on the streets here.

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