They sort it, appraise it and arrange it in great piles, selling whatever they can, burning the rest.
They live off garbage. And in it.
Using rickety wooden carts pulled by donkeys, the zabaleen collect 1,800 tons of household waste every day throughout Cairo. Without them, the largest city in the Arab world would be ankle-deep in fish skeletons, orange peels, bottle caps and empty Marlboro packages.
The zabaleen do not get paid for providing this service.
They get the garbage.
Like most of his fellow zabaleen, Fawzi Attallah, 45, was born into this bondage. His father and his uncles made their livings off the leavings of Cairo. He began working alongside them at age 10.
Today, his two eldest sons - Eid, 8, and Ayman, 10 - accompany him as he makes his rounds in his rubbish cart, flailing at his donkeys with a piece of discarded electrical cable.
"I don't like it, but what else can I do?" Attallah said one afternoon last week as he and his family sorted through the day's haul. "I have to feed my sons. This is the only job I can do. I don't have any way out."
The zabaleen have been described as "Egypt's untouchables." Government officials prefer not to talk about their plight. News photographers are warned not to take pictures of their trash-laden carts as they rattle down the streets of Cairo.
Almost all of the zabaleen are Coptic Christians. Their association with garbage and the raising of pigs, a species regarded as unclean by the country's Muslim majority, has placed them beyond the pale of respectability in the eyes of many Egyptians.
The zabaleen collect about 40 percent of the trash generated in Cairo each day. A smaller quantity, about 1,600 tons per day, is picked up by municipal sanitation workers. The government cannot afford to extend public collection to the areas now served by the zabaleen. So it tolerates them - barely.
Over the years, the government has shunted the garbage people from one corner of Cairo to another, resettling them in ever-more-remote locations in hopes of finding a place where their activities will not offend anyone.
There are seven zabaleen settlements in the capital, with a total population of about 24,000. The largest of these, with 12,000 inhabitants, sprawls across a barren ocher hilltop on the eastern edge of Cairo known as the Moqattam.
The smell of the place assaults the senses with near-physical force. Most of the households have no running water or electricity. Families sit down to their meals a few feet from where pigs, goats and geese feast on heaps of ripening rubbish.
The zabaleen complain of chronic stomach and lung ailments. Few of them have ever handled a bar of soap. A study conducted several years ago found that one in every four of their children died within a year of birth.
The zabaleen work seven days a week, starting their rounds well before
dawn. The three-mile trip from the Moqattam to downtown Cairo can take three hours. They return in early afternoon, empty their carts into their houses and start sorting.
By one estimate, 80 percent of what they collect is reused in one way or another. Outside their shanties are great heaps of cattle bones, piles of plastic sandals and bales of discarded clothing, all waiting to be sold to recycling contractors for the equivalent of a fraction of a cent per pound.
Few of the zabaleen can imagine any other way of life.
"I have no complaints," Nasif Bagouri, 59, head of an extended family of rubbish handlers, said the other day. "I can survive with this job, thank God. Whether I like it or not, it's what I do."
Inside the family's two-room dwelling, Amin Bagouri, 40, the eldest of Nasif's 12 children, was busy sorting a fresh load of refuse. Squeals rang out
from an adjacent pigpen fashioned from tree branches and rusted aluminum.
In the distance, the hotels and office towers of downtown Cairo shimmered, dreamlike, in the afternoon sun.
Within this nightmare world, a social heirarchy has taken shape. The people who process and recycle trash regard themselves as being a cut above those who simply collect it.
Lamey Youseff Bashout, 57, his wife and their six children strip and flatten aluminum cans in a workshop next to their house. The sale of this material to recycling contractors brings in 60 to 70 Egyptian pounds ($30 to $35) per month.
The Bashouts do not have running water, but they do have a small stereo system, an automatic clothes washer and the electricity to operate both. Their children, unlike those in many zabaleen families, have shoes.
The Bashouts do not collect the cans they process. They buy them from other zabaleen for three pounds per cartload. Lamey Bashout is emphatic on this point. Collecting trash is another line of work.
"We don't do that," he said.
Many of the zabaleen are the sons of tenant farmers from Upper Egypt who came to Cairo in hopes of finding a better life and wound up hauling trash. Irian Bekheet's father made the trek 26 years ago, expecting to find work as a manual laborer. Two years later, he sent a message back to his family in the city of Sohag in Upper Egypt. "There is work," he said. He did not say what kind.
Bekheet, now 35, said that when he and his three brothers got to Cairo, they initially refused to work as zabaleen. They spent a year looking for other employment, but found nothing. Finally, they relented and joined their father on his rubbish cart.
Today, Bekheet collects garbage along two streets in the working-class district of Helmeya. The glass, cloth and plastic that he scavenges from his loads bring in 70 to 80 Egyptian pounds per month.
Bekheet hates the job, but sees no escape from it. He cannot read or write. The family sold its house and property in Sohag long ago.
"There is nothing to go back to," he said.
He and the other zabaleen are part of a garbage-collection system established about 100 years ago by desert people who migrated to Cairo from the remote Egyptian oases of Kharga and Dakhla.
The newcomers, called wahayet, Arabic for "oasis dwellers," pay building owners throughout Cairo for the right to collect trash - and a monthly fee - from apartment dwellers.
In the 1930s, the descendants of the current zabaleen began migrating to Cairo from Upper Egypt. The wahayet, anxious to turn over the dirty part of the business to someone else, recruited them as trash collectors.
For many years, the wahayet charged the zabaleen a fee for the right to gather garbage on their assigned routes. That practice has ended, but the wahayet still supervise the system and pocket the fees - ranging from one to three pounds per month - paid by apartment dwellers. Through their trade association, the zabaleen have demanded a percentage of these revenues. From time to time, the collectors and their overlords come to blows over the issue.
Bekheet, the rubbish collector from Sohag, is appalled by what he regards as the unfairness of it all.
"The wahayet live in decent, clean areas," he said. "When they finish work, they can go home and wash up. They're leading livable lives." Still, the zabaleen keep working. They cannot afford to go on strike, said Bekheet, who has a wife and three children to support.
"It's hard enough to get by as it is," he said.
Bad as the plight of the zabaleen are, it used to be much worse.
For many years, the families living on the Moqattam had no houses at all. They squatted directly on the rubbish, like flies.
In the wake of a series of destructive fires on the Moqattam in the 1970s, a Catholic nun, Sister Emmanuelle, persuaded the government to build a school for the zabaleen, pave some roads and make other improvements.
Since then, Sister Emmanuelle and an Egyptian consulting firm have worked with private foundations and the Egyptian government to help some of the zabaleen go into the recycling business.
With financial aid from the foundations, some zabaleen have purchased machines for shredding rags, producing nails from scrap metal and recasting waste plastic into spoons, toys, electrical insulation and other products.
The zabaleen and the wahayet, moreover, have agreed to pool their resources to purchase garbage trucks to replace the donkey carts. Plans call for zabaleen to be hired as salaried drivers and attendants on the trucks. Gradually, the wooden carts are to be removed from Cairo's streets, fulfilling a longstanding wish of government officials.
It seems unlikely that the zabaleen will ever disappear, however. Saweeres Nasif, 41, standing in his rubbish cart one afternoon last week, said he could not envision any life outside the garbage trade.
"If I could, I'd leave this job today," he said. "I wouldn't wait until tomorrow. But it's my job. It's how I earn my money."
He glanced at his two sons, aged 11 and 16.
"They'll take over someday," he said.