"I mention Baghdad first of all because it is the heart of Iraq, and, with no equal on earth either in the Orient or the Occident, it is the most extensive city in area,in importance, in prosperity, in abundance of water, and in healthful climate.
It is inhabited by the most diverse individuals, both city people and country folk; people emigrate to it from all countries, both near and far; and everywhere there are who have preferred it to their own country. All the peoples of the world have theirmen own neighborhoods there, their trade and commercial centers; that is why there is gathered together here what does not exist in any other city in the world. It stretches out on the two banks of those two large rivers, the Tigris and the Euphrates, and watches commercial
products and staples flow to it on land and on water. For it is with great ease that each commercial object is transported endlessly from East and West, from Moslem and non-Moslem regions.(read further into Al-Ya'qubi description of Baghdad?)

The Building of Baghdad

Wide avenues, bordered by brick and plaster arcades, ran in four directions from the center of the city to the city's entrances. One could enter each through a vaulted passage- way, built of baked bricks and plaster, in the outer wall. A roadway of hard stone led from there to a passageway through the main wall which was closed by iron gates. The passageway had small windows which let light in but kept rain out. Each of the four gates was vaulted, and each of the en tranceways of the main wall was surmounted by an immense gilt cupola, an observation tower on teak columns. Each tower had rooms which were reached by a ramp.
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