Greater Cairo

The Greater Cairo Area (GCA; ) is the largest metropolitan area in Egypt, the largest urban area in Africa, the Middle East, and the Arab world, and the 6th largest metropolitan area in the world. It consists of all cities in the Cairo Governorate as well as Giza, 6th of October, Sheikh Zayed City in the Giza Governorate and Shubra El Kheima and Obour in the Qalyubia Governorate, with a total population estimated at 20,901,000; area: 1,709 km2; density: 10,400/km2.
Climate.
The Greater Cairo Area and its surrounding region is classified as hot desert climate (BWh) in Köppen-Geiger classification, as all of Egypt. Cairo and its surrounding region have very similar day to day temperatures; however, the less populated parts at the east and the west do not have the urban heat, which makes them more prone to have soft hail.
Urban issues.
60% of all informal houses in Egypt are located in the Greater Cairo area.