Egypt has 81,527,172 people as of 2008.
Cairo has over 20,000,000 residents, I would say it is safe to add on another 2-5 million to that number.
Donkey carts have been outlawed in downtown Cairo in an effort to improve traffic.
The new "Ring Road" is 100 kilometers (62 miles) and as the name implies goes around the Cairo/Giza metropolis.
Cairo is considered a "Mega City," joining the likes of Mumbai, Mexico City, New York, Tokyo, and others.
One half of all hospital beds are found in Cairo
One half of all university desks are found in Cairo
If Cairo were a sovereign nation it would be the 5th largest Arab country
Alexandria, the second largest city in Egypt, in only 30 percent the size of Cairo.
There are over 2,000,000 cars in the streets of Cairo, 60 percent of which are over ten years old.
The Great Pyramids of Giza, sort of Cairo, are the only remaining monument of the Seven Wonders of the Ancient World.
An estimated 9,351 under-age marriages take place in Egypt, with the vast majority of them taking place in Cairo.
A Greek papyrus from 163 B.C. mentions girls in Egypt undergoing female circumcision and the practice is widely accepted to have originated in Egypt and the Nile valley at the time of the Pharaohs. Although both Al Azhar religious officials and Coptic Pope state it has no basis in religious scripture, practice, or law and it should be not practiced.
Mohsen Reda, an Egyptian Member of Parliament, was asked about the prevalence of sexual harassment against women in Egypt and was quoted as as saying that women should be dressed more modestly as “a lot of our youth can’t afford marriage so it is only normal for some harassment to take place.”