The historic citadel of Erbil is believed to have been continuously inhabited for more than 6000 years. Although there are no ancient references as to how many people actually lived within the town one may assume its maximum capacity was around 5000 people. This figure gives a population density of around 500 inhabitants per hectare- regarded as very high by modern standards but not by the standards of traditional Islamic cities.
The residential fabric of the citadel town occupied over 75% of the total surface area. The rest was taken up by some public buildings such as mosques, a hammam, takyas (hospices), shops, and narrow alleyways for pedestrian circulation. The number of houses was about 500 which meant that on average there were some 10 people living per house.
The population of the citadel must have formed a cohesive and a strongly conformist and conservative community. This cohesion, which partly came from tribal associations and partly from blood relations, was also enforced by Islamic traditions and values. Such values strongly emphasized the need to help relatives and respect neighbors as if they were relatives.