The Cairo Metro system sprawls across the city, delivering an estimated 3.6 million passengers per day over three different lines and approximately 78 kilometers (49 miles) of train track, both above ground and below the city center.

In a city known, as much as anything, for its dysfunction, the Cairo Metro stands as a singular achievement. It's reliable, well-maintained and relatively clean. And it may be the only place in Egypt where no-smoking rules are actually enforced. At 1 Egyptian pound (13 cents) per ticket, the Metro is a bargain even in a country like Egypt where nearly half the population of 90 million lives near or below the poverty line.

All Photos by Heba Elkholy/ AP