In the '90s, my interest and passion for transitional art forms led me to a new form, which came from a squatter camp outside Durban.

Stewart Brand on squatter cities

There's no unemployment in squatter cities. Everyone works.

So, that's Kibera, the largest squatter community in Nairobi.

Hey, that's a single family home in the squatter community.

The numbers are considerable. A billion live in the squatter cities now.

And this is Sultanbelyi, which is one of the largest squatter communities in Istanbul.

And then you finally get squatter homes like this, which is built on the suburban model.

This is the squatter community in Sanjay Gandhi National Park in Bombay, India, what's called Mumbai these days.

Because in town this is the bustling squatter city of Kibera, near Nairobi they see action. They see opportunity.

Camp Crame

Facilities and Camp

So my father and mother ended up in a sort of concentration camp, labor camp.

Afterwards, the camp just having the camp increases immunization from six percent to 17 percent.

And then Camp Four is the highest camp that's 3,000 feet short of the summit.

A German prison camp.

Refugee camp in Darfur.

A handful of camps, however, still require a reregistration process. Notable among these are Kalma camp and Al Battery camp (Kass), both in Southern Darfur, and Ardamata camp in Western Darfur.

This is on the way up from Camp Three to Camp Four, moving in, up through the clouds.

The mainly southern internally displaced persons living in squatter areas and camps around Khartoum are still subject to forced relocations by the authorities, who often conduct violent search operations.

Camp One, 2,000 feet higher.

Okay. This is Camp One.

c) Development of camp infrastructure

Camp Alpha, anti aircraft gun

Following unrest in Kalma camp on 19 May, a ban was imposed on commercial traffic to and from the camp.

So, it's like base camp Everest.

And this is at Camp Four.

Facilities and Camp Management Services Unit

It happened at evening that quail came up and covered the camp and in the morning the dew lay around the camp.

Video Girl Duke IIMA Camp. Whenever we see that IIMA, it was such a pride for us to go to that camp.

It happened at evening that quail came up and covered the camp and in the morning the dew lay around the camp.

The same officers rotate from camp to camp to avoid establishing close relationships with the recruits undergoing military training at the camps.

The German camp guards, they've got bored.

This is a view of base camp.

Over the following years, the camp expanded.

Robert Neuwirth, author of Shadow Cities, finds the world s squatter sites where a billion people now make their homes to be thriving centers of ingenuity and innovation. He takes us on a tour.

One bitterly cold March day, I joined a few friends on a trip to the former camp. Built in the early 1940s as a regular labor camp, Perm 36 was converted into a concentration camp for political prisoners in 1972.

The humanitarian situation in Kalma camp also remains worrying, with conditions in the overcrowded camp deteriorating and camp management rendered increasingly difficult by the expansion of its size and the lack of trust between internally displaced persons and local authorities.

Both you shall put male and female outside of the camp that they not defile their camp, in the midst of which I dwell.

Both you shall put male and female outside of the camp that they not defile their camp, in the midst of which I dwell.

So the ark of the LORD compassed the city, going about it once and they came into the camp, and lodged in the camp.

So the ark of the LORD compassed the city, going about it once and they came into the camp, and lodged in the camp.

At Iridimi Camp, three refugees were shot when refugees opposed to a re registration exercise clashed with Chadian police responsible for providing camp security.

At first, we were safe in the camp.

You've got to see this Bible Boot Camp.