On the Mexican side, where the population is more than a million, little wisps of gray smoke rise from wood fires that heat homes in vast slums.

Chalabi is standing inside a tent in Sadr City, the vast Shiite slum of eastern Baghdad.

To expand its reach, Nyumbani has an outreach component, which takes the orphanage's health specialists and counselors into Nairobi's vast slums.

There was only a limited unrest in the vast slum of Saddam City, while the rest of the capital remained calm.

The rapid expansion of the population of industrial cities and towns in the early years of the nineteenth century led to the growth of vast urban slums.

Once a city of palm-shaded boulevards lined with restaurants and cafes, Basra now resembles a vast, desiccated slum.

Chávez ordered all branches of the military to devise programs to combat poverty and to further civic and social development in Venezuela's vast slum and rural areas.

The Shiite Muslim community stretches 400 miles south from Sadr City, a vast slum on the northern edge of Baghdad.

For example, American forces have moved into only a small portion of Sadr City, the vast slum on the city's east side that is a Shiite stronghold.

But it also has vast slums stretching from the historic old town to surrounding mountain ridges, where the poorest of the poor struggle to survive.