How loud is Cairo?

Cairo earned its reputation as one of the world’s loudest cities with data: researchers at Egypt’s National Research Centre measured average daytime noise in central Cairo at roughly 85 dB — a level NIOSH treats as the limit for a full working day — and described living in the city centre as acoustically equivalent to working inside a factory.

The mix is distinctive. A car-dense road network threads between buildings that reflect sound back onto the street; horns function as language; wedding processions, street vendors and café crowds run late into the night in a city that genuinely does not sleep.

One famous source of massed sound has actually been tamed: the call to prayer from Cairo’s thousands of mosques, once a minute-long citywide chorus of competing loudspeakers, was unified by the religious endowments ministry onto a single synchronised broadcast — one of the more striking noise-management interventions anywhere. The traffic, so far, has resisted equivalent treatment.

Cairo noise: the specifics

• A 2007 Egyptian National Research Centre study measured ~85 dB average daytime noise downtown.
• The call to prayer across Cairo’s mosques was unified onto a synchronised single broadcast to cut loudspeaker noise.
• Dense, hard-surfaced streets reflect traffic noise, keeping evening levels close to daytime ones.
• Estimated 75–90 dB daytime range vs. the WHO’s 53 dB L_den guideline — roughly 30 dB over.