Giza is the third-largest city in Egypt by area after Cairo and Alexandria; and fourth-largest city in Africa by population after Kinshasa, Lagos, and Cairo. It is the capital of Giza Governorate with a total population of 4,872,448 in the 2017 census. It is located on the west bank of the Nile opposite central Cairo, and is a part of the Greater Cairo metropolis. Giza lies less than 30 km (18.64 mi) north of Memphis, which was the capital city of the unified Egyptian state during the reign of pharaoh Narmer, roughly 3100 BC.